U.S. patent number 11,133,998 [Application Number 16/524,570] was granted by the patent office on 2021-09-28 for method, apparatus, and system for measuring network delay.
This patent grant is currently assigned to Huawei Technologies Co., Ltd.. The grantee listed for this patent is HUAWEI TECHNOLOGIES CO., LTD.. Invention is credited to Wenjun Chang, Wei Fang, Hongming Liu.
United States Patent |
11,133,998 |
Fang , et al. |
September 28, 2021 |
Method, apparatus, and system for measuring network delay
Abstract
A method, an apparatus, and a system for measuring a network
delay are disclosed. The method includes: acquiring delay
measurement information obtained by measuring a service flow by at
least one target logical port TLP, where the delay measurement
information includes: timestamp information, a service flow
identifier, and a TLP identifier; and transmitting the delay
measurement information to a measurement control point MCP, so that
the MCP determines details about a network delay according to the
timestamp information, the service flow identifier, and the TLP
identifier. Embodiments of the present application further provide
an apparatus and a system for measuring a network delay.
Embodiments of the present application achieve direct and accurate
delay measurement of a service flow in scenarios of point to point
transmission or point to multipoint transmission on the network,
and reflect details about a real delay of the service flow.
Inventors: |
Fang; Wei (Beijing,
CN), Liu; Hongming (Shenzhen, CN), Chang;
Wenjun (Beijing, CN) |
Applicant: |
Name |
City |
State |
Country |
Type |
HUAWEI TECHNOLOGIES CO., LTD. |
Guangdong |
N/A |
CN |
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Assignee: |
Huawei Technologies Co., Ltd.
(Shenzhen, CN)
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Family
ID: |
48316009 |
Appl.
No.: |
16/524,570 |
Filed: |
July 29, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190349279 A1 |
Nov 14, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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14669513 |
Aug 6, 2019 |
10374925 |
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PCT/CN2012/082490 |
Sep 29, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L
7/0037 (20130101); H04L 43/0852 (20130101); H04L
43/106 (20130101) |
Current International
Class: |
H04L
12/26 (20060101); H04W 56/00 (20090101); H04L
12/851 (20130101); H04L 7/00 (20060101) |
Field of
Search: |
;370/252,247 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101056215 |
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Oct 2007 |
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CN |
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101854268 |
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Oct 2010 |
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CN |
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1684463 |
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Jul 2006 |
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EP |
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2498445 |
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Sep 2012 |
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EP |
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2012059138 |
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May 2012 |
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WO |
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Other References
R Braden, Editor, Requirements for Internet Hosts--Communication
Layers, Network Working Group Internet Engineering Task Force, RFC
1122, Oct. 1989. cited by applicant .
K. Nichols et al , Definition of the Differentiated Services Field
(DS Field) in the IPv4 and IPv6 Headers, Network Working Group,
RFC2474 Dec. 1998. cited by applicant .
K. Ramakrishnan et al, The Addition of Explicit Congestion
Notification (ECN) to IP, Network Working Group, RFC3168, Sep.
2001. cited by applicant .
C. Demichelis et al, IP Packet Delay Variation Metric for IP
Performance Metrics (IPPM), Network Working Group, RFC 3393, Nov.
2002. cited by applicant .
S. Shalunov et al, A One-way Active Measurement Protocol (OWAMP),
Network Working Group, RFC4656, Sep. 2006. cited by applicant .
K. Hedayat et al, A Two-Way Active Measurement Protocol (TWAMP),
Network Working Group, RFC 5357, Oct. 2008. cited by applicant
.
D. Frost et al, Packet Loss and Delay Measurement for MPLS
Networks, Internet Engineering Task Force (IETF), RFC6374, Sep.
2011. cited by applicant .
D. Frost, Ed et al, A Packet Loss and Delay Measurement Profile for
MPLS-Based Transport Networks, Internet Engineering Task Force
(IETF), RFC6375, Sep. 2011. cited by applicant .
ITU-T G.8013/Y.1731, Series G: Transmission Systems and
Media,Digital Systems and Networks Packet over Transport
aspects--Ethernet over Transport aspects Series Y: Global
Information Infrastructure, Internet Protocol Aspects and
Next-Generation Networks Internet protocol aspects--Operation,
administration and maintenance, 2012.5. cited by applicant .
A. Tempia Bonda et al:"A packet based method for passive
performance monitoring draft-tempia-opsawg-p3m-02.txt", Jan. 17,
2013 ,total 23 pages. cited by applicant .
IEEE Std 1588--2008, IEEE Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and control
Systems; IEEE Instrumentation and Measurement Society; Sponsored by
the Technical Committee on Sensor Technology (TC-9), Jul. 24, 2008,
total 289 pages. cited by applicant.
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Primary Examiner: Nawaz; Asad M
Assistant Examiner: Harley; Jason A
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser.
No. 14,669/513, filed on Mar. 26, 2015. The U.S. patent application
Ser. No. 14,669/513 is a continuation of International Application
No. PCT/CN2012/082490, filed on Sep. 29, 2012. All of the
aforementioned patent applications are hereby incorporated by
reference in their entireties.
Claims
What is claimed is:
1. A method for measuring a network delay of a network, comprising:
acquiring, by a data collecting point (DCP) managing an upstream
target logical port (TLP), transmit-end delay measurement
information obtained by measuring a service flow by the upstream
TLP that is transmitted through the network, wherein the
transmit-end delay measurement information comprises transmit-end
timestamp information, and a service flow identifier of the service
flow, and wherein the transmit-end delay measurement information is
corresponding to a data packet including a delay measurement flag;
acquiring, by a DCP managing a downstream TLP, receive-end delay
measurement information obtained by measuring the service flow by
the downstream TLP, wherein the receive-end delay measurement
information comprises receive-end timestamp information, and the
service flow identifier of the service flow, and wherein the
receive-end delay measurement information is corresponding to the
data packet including the delay measurement flag; transmitting, by
the DCP managing the upstream TLP, the transmit-end delay
measurement information to a measurement control point (MCP); and
transmitting, by the DCP managing the downstream TLP, the
receive-end delay measurement information to the MCP, wherein the
transmit-end delay measurement information and the receive-end
delay measurement information are used to determine a network delay
of the network.
2. The method according to claim 1, wherein, within each
measurement period one data packet is added with the delay
measurement flag.
3. The method according to claim 1, further comprising: when a
measurement period for measuring the service flow ends, acquiring,
by the DCP managing the upstream TLP, a measurement period
identifier of the measurement period; transmitting, by the DCP
managing the upstream TLP, the measurement period identifier to the
MCP; and acquiring, by the DCP managing the downstream TLP, start
time of the measurement period, wherein when a difference between
the start time and the receive-end timestamp information is not
more than a preset duration, the receive-end delay measurement
information corresponds to the measurement period identifier, and
when the difference between the start time and the receive-end
timestamp information is greater than the preset duration, the
measurement period identifier is increased by 1, the timestamp
information corresponds to a next measurement period, and the
measurement period identifier is transmitted to the MCP.
4. The method according to claim 1, further comprising: acquiring,
by the DCP managing the downstream TLP, a measurement packet
transmitted by the upstream TLP and received by the downstream TLP,
and arrival timestamp information of the measurement packet
generated when the measurement packet arrives at the downstream
TLP, wherein the measurement packet comprises transmit-end
timestamp information; determining, by the DCP managing the
downstream TLP, that the transmit-end timestamp information and the
receive-end timestamp information correspond to a same data packet,
when determining that the arrival timestamp information and the
receive-end timestamp information correspond to a preset duration
range; and transmitting a determination result to the MCP.
5. A method for measuring a network delay of a network, comprising:
adding, by an upstream target logical port (TLP), a delay
measurement flag to a data packet of a service flow that is
transmitted through the network; acquiring, by the upstream TLP,
transmit-end delay measurement information of the data packet to
which the delay measurement flag is added, wherein the transmit-end
delay measurement information comprises transmit-end timestamp
information, and a service flow identifier of the service flow;
identifying, by a downstream TLP, the data packet to which the
delay measurement flag is added; and acquiring, by the downstream
TLP, receive-end delay measurement information of the data packet,
wherein the receive-end delay measurement information comprises
receive-end timestamp information and the service flow identifier
of the service flow.
6. The method according to claim 5, wherein within each measurement
period one data packet is added with the delay measurement flag by
the upstream TLP.
7. The method according to claim 5, wherein the adding, by an
upstream TLP, the delay measurement flag to the data packet of the
target service flow comprises: adding the delay measurement flag in
at least one of a reserved bit of type of service (TOS) or a
reserved bit of Flags in an IP header of the data packet.
8. A method for measuring a network delay of a network, comprising:
receiving, by a measurement control point (MCP), transmit-end delay
measurement information transmitted by a data collecting point
(DCP) corresponding to an upstream target logical port (TLP) and
receive-end delay measurement information transmitted by a DCP
corresponding to a downstream TLP, wherein the transmit-end delay
measurement information comprises transmit-end timestamp
information and a service flow identifier of a service flow which
is transmitted through the network; and the receive-end delay
measurement information comprises receive-end timestamp information
and the service flow identifier of the service flow, and wherein
the transmit-end delay measurement information and the receive-end
delay measurement information are corresponding to a data packet
including a delay measurement flag; and determining, by the MCP,
network delay of the network according to the transmit-end delay
measurement information and the receive-end delay measurement
information.
9. The method according to claim 8, wherein within each measurement
period one data packet is added with the delay measurement
flag.
10. The method according to claim 8, further comprising: receiving,
by the MCP, a measurement period identifier transmitted by the DCP
managing the upstream TLP; receiving, by the MCP, a measurement
period identifier transmitted by the DCP managing the downstream
TLP; determining, by the MCP according to the measurement period
identifier transmitted by the DCP managing the upstream TLP and the
measurement period identifier transmitted by the DCP managing the
downstream TLP, that the transmit-end delay measurement information
and the receive-end delay measurement information correspond to a
same measurement period; and determining, by the MCP, the network
delay according to the transmit-end delay measurement information
and the receive-end delay measurement information.
11. A data collecting point (DCP), comprising: a processor, wherein
when the DCP is a DCP managing an upstream target logical port
(TLP), the processor is configured to cause the DCP to: acquire
transmit-end delay measurement information obtained by measuring a
transmitted service flow by the upstream TLP that is transmitted
through a network, wherein the transmit-end delay measurement
information comprises transmit-end timestamp information and a
service flow identifier of the transmitted service flow, and
wherein the transmit-end delay measurement information is
corresponding to a data packet including a delay measurement flag;
and transmit the transmit-end delay measurement information to the
MCP; when the DCP is a DCP managing a downstream TLP, the processor
is configured to cause the DCP to: acquire receive-end delay
measurement information obtained by measuring a received service
flow by the downstream TLP that is transmitted through the network,
wherein the receive-end delay measurement information comprises
receive-end timestamp information, and a service flow identifier of
the received service flow, and wherein the receive-end delay
measurement information is corresponding to a data packet including
a delay measurement flag; and transmitting the receive-end delay
measurement information to the MCP, wherein the transmit-end delay
measurement information and the receive-end delay measurement
information are used to determine a network delay of the
network.
12. The DCP according to claim 11, wherein within each measurement
period one data packet is added with the delay measurement
flag.
13. The DCP according to claim 11, wherein the processor is further
configured to cause the DCP to: when the DCP is the DCP managing
the upstream TLP, and when a first measurement period for measuring
the transmitted service flow ends, acquire a first measurement
period identifier of the first measurement period, and transmit the
first measurement period identifier to the MCP; when the DCP is the
DCP managing the downstream TLP, and when a second measurement
period for measuring the received service flow starts, acquire
start time of the second measurement period, wherein when a
difference between the start time and the receive-end timestamp
information is not more than a preset duration, the receive-end
delay measurement information corresponds to a second measurement
period identifier of the second measurement period, and when the
difference between the start time and the receive-end timestamp
information is greater than the preset duration, the second
measurement period identifier is increased by 1, the receive-end
timestamp information corresponds to a next measurement period, and
the second measurement period identifier is acquired; and transmit
the second measurement period identifier to the MCP.
14. The DCP according to claim 11, wherein when the DCP is the DCP
managing the downstream TLP, the processor is further configured to
cause the DCP to: acquire a measurement packet transmitted by
another upstream TLP and received by the downstream TLP, and
arrival timestamp information of the measurement packet generated
when the measurement packet arrives at the downstream TLP, wherein
the measurement packet comprises transmit-end timestamp
information; determine that the transmit-end timestamp information
in the measurement packet and the receive-end timestamp information
correspond to a same data packet, when determining that the arrival
timestamp information and the receive-end timestamp information
correspond to a preset duration range; and transmit a determination
result to the MCP.
15. A target logical port (TLP), comprising: a port; a processor in
communication with the port, wherein when the TLP is an upstream
TLP, the processor is configured to: add a first delay measurement
flag to a first data packet of a first service flow transmitted
through the port; and acquire transmit-end delay measurement
information of the first data packet to which the first delay
measurement flag is added, wherein the transmit-end delay
measurement information comprises transmit-end timestamp
information and a service flow identifier of the first service
flow, wherein when the TLP is a downstream TLP, the processor is
configured to: identify a second data packet to which a second
delay measurement flag is added, acquire receive-end delay
measurement information of the second data packet, and wherein the
receive-end delay measurement information comprises receive-end
timestamp information and a service flow identifier of a service
flow that is transmitted through the port and that comprises the
second data packet.
16. The TLP according to claim 15, wherein within each measurement
period one data packet is added with a delay measurement flag by
the upstream TLP.
17. The TLP according to claim 15, wherein the first delay
measurement flag is added into at least one of: a reserved bit of
type of service (TOS) or a reserved bit of Flags in an IP header of
the first data packet.
18. A measurement control point (MCP), comprising: a processor,
wherein the processor is configured to cause the MCP to: receive
transmit-end delay measurement information transmitted by a data
collecting point (DCP) corresponding to an upstream target logical
port (TLP) and receive-end delay measurement information
transmitted by a DCP corresponding to a downstream TLP, wherein the
transmit-end delay measurement information comprises transmit-end
timestamp information and a service flow identifier of a service
flow that is transmitted through a network, and wherein the
receive-end delay measurement information comprises receive-end
timestamp information and the service flow identifier of the
service flow, and wherein the transmit-end delay measurement
information and the receive-end delay measurement information are
corresponding to a data packet including a delay measurement flag;
and determine a network delay of the network according to the
transmit-end delay measurement information and the receive-end
delay measurement information.
19. The TLP according to claim 18, wherein within each measurement
period one data packet is added with the delay measurement
flag.
20. The MCP according to claim 18, wherein the processor is further
configured to cause the MCP to: receive a measurement period
identifier transmitted by the DCP managing the upstream TLP, and a
measurement period identifier transmitted by the DCP managing the
downstream TLP; determine, according to the measurement period
identifier transmitted by the DCP managing the upstream TLP and the
measurement period identifier transmitted by the DCP managing the
downstream TLP, that the transmit-end delay measurement information
and the receive-end delay measurement information correspond to a
same measurement period; and determine the network delay according
to the transmit-end delay measurement information and the
receive-end delay measurement information.
Description
TECHNICAL FIELD
The present application relates to communications technologies, and
in particular, to a method, an apparatus, and a system for
measuring a network delay.
BACKGROUND
With continuous development of network information technologies, IP
(Internet Protocol)-based networks are prevailing. Under such
circumstances, how to conduct a delay performance quality
evaluation for IP-based services has become an increasingly
prominent problem.
In the prior art, a delay of a network service flow is measured
mainly by inserting a dedicated delay measurement packet into a
measurement end, where the delay measurement packet carries
timestamps of a transmitting end and a receiving end. A delay
result of the network service flow is then calculated according to
receiving timestamp and transmitting timestamp in the delay
measurement packet.
However, because the prior art employs indirect measurement of the
delay measurement packet, delay performance of the network service
flow cannot be truly and accurately reflected.
SUMMARY
Embodiments of the present application provide a method, an
apparatus, and a system for measuring a network delay, to achieve
measurement of a delay of a network service flow.
According to one aspect, an embodiment of the present application
provides a method for measuring a network delay, including:
acquiring delay measurement information obtained by measuring a
service flow by at least one target logical port TLP, where the
delay measurement information includes: timestamp information, a
service flow identifier, and a TLP identifier; and
transmitting the delay measurement information to a measurement
control point MCP, so that the MCP determines details about a
network delay according to the timestamp information, the service
flow identifier, and the TLP identifier.
Optionally, in the foregoing method for measuring a network delay,
the acquiring delay measurement information obtained by measuring a
service flow by at least one TLP, may include: the acquiring delay
measurement information obtained by measuring a service flow by at
least one TLP includes:
acquiring, by a data collecting point DCP managing an upstream TLP,
transmit-end delay measurement information obtained by measuring a
transmitted service flow by at least one upstream TLP; and
acquiring, by a DCP managing a downstream TLP, receive-end delay
measurement information obtained by measuring a received service
flow by at least one downstream TLP;
the transmitting the delay measurement information to an MCP
includes:
transmitting, by the DCP managing the upstream TLP, the
transmit-end delay measurement information to the MCP, where the
transmit-end delay measurement information includes: transmit-end
timestamp information, a service flow identifier, and a TLP
identifier; and
transmitting, by the DCP managing the downstream TLP, the
receive-end delay measurement information to the MCP, where the
receive-end delay measurement information includes: receive-end
timestamp information, a service flow identifier, and a TLP
identifier.
Optionally, the forgoing method for measuring a network delay may
include:
when a measurement period ends, acquiring, by the DCP managing the
upstream TLP, a measurement period identifier, and transmitting the
measurement period identifier to the MCP; and
acquiring, by the DCP managing the downstream TLP, start time of
the measurement period; where if a difference between the start
time and the timestamp information is less than or equal to a
preset duration, the receive-end delay measurement information
pertains to measurement information corresponding to the
measurement period identifier; and if the difference between the
start time and the timestamp information is greater than the preset
duration, the measurement period identifier is increased by 1, the
timestamp information pertains to a next measurement period, and
the measurement period identifier is transmitted to the MCP.
Optionally, in the forgoing method for measuring a network delay,
the preset duration is 2/3 of a duration of the measurement
period.
Optionally, the forgoing method for measuring a network delay may
include:
performing, by the DCP managing the upstream TLP, time
synchronization with the upstream TLP by using the NTP or an IEEE
1588v2 clock; performing, by the DCP managing the downstream TLP,
time synchronization with the downstream TLP by using the NTP or an
IEEE 1588v2 clock; and performing, by the DCP managing the upstream
TLP, time synchronization with the DCP managing the downstream TLP
by using the NTP or an IEEE 1588v2 clock.
Optionally, the forgoing method for measuring a network delay may
include:
acquiring, by the DCP managing the downstream TLP, a measurement
packet transmitted by the upstream TLP and received by the at least
one downstream TLP, and arrival timestamp information of the
measurement packet, which is generated when the measurement packet
arrives at the downstream TLP, where the measurement packet
includes: transmit-end timestamp information; and
determining, by the DCP managing the downstream TLP, whether the
arrival timestamp information and the receive-end timestamp
information pertain to a preset duration range; and if the arrival
timestamp information and the receive-end timestamp information
pertain to the preset duration range, determining that the
transmit-end timestamp information and the receive-end timestamp
information pertain to a same data packet, and transmitting a
result of the determining to the MCP.
Optionally, in the forgoing method for measuring a network delay,
the transmit-end delay measurement information further includes:
transmit-end service flow characteristic information and a
transmit-end fragment reassembly identifier; and the receive-end
delay measurement information further includes: receive-end service
flow characteristic information and a receive-end fragment
reassembly identifier, so that the MCP determines, according to the
transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, that the transmit-end timestamp
information and the receive-end timestamp information are timestamp
information corresponding to a same service flow.
According to another aspect, an embodiment of the present
application provides a method for measuring a network delay,
including:
identifying a service flow according to service flow characteristic
information, and determining whether the service flow is a target
service flow;
if the service flow is a target service flow, adding a delay
measurement flag to a data packet of the service flow, and
acquiring data packet delay measurement information corresponding
to the delay measurement flag; and
determining delay measurement information, where the delay
measurement information includes: timestamp information, a service
flow identifier, a TLP identifier, so that after acquiring the
delay measurement information, a DCP transmits the delay
measurement information to an MCP.
Optionally, in the method for measuring a network delay, the adding
a delay measurement flag to a data packet of the service flow, and
acquiring data packet delay measurement information corresponding
to the delay measurement flag includes:
adding, by an upstream TLP, a delay measurement flag to the data
packet of the target service flow, and acquiring transmit-end delay
measurement information of the data packet corresponding to the
delay measurement flag, where the transmit-end delay measurement
information includes: transmit-end timestamp information, a service
flow identifier, and a TLP identifier, so that after acquiring the
transmit-end delay measurement information, a DCP managing the
upstream TLP transmits the transmit-end delay measurement
information to the MCP; and
when identifying the data packet to which the delay measurement
flag is added, acquiring, by a downstream TLP, receive-end delay
measurement information of the data packet corresponding to the
delay measurement flag, where the receive-end delay measurement
information includes: receive-end timestamp information, a service
flow identifier, and a TLP identifier, so that after acquiring the
receive-end delay measurement information, a DCP managing the
downstream TLP transmits the receive-end delay measurement
information to the MCP.
Optionally, the method for measuring a network delay further
includes:
before adding the delay measurement flag to the data packet of the
target service flow, performing, by the upstream TLP, time
synchronization with the DCP managing the upstream TLP by using the
NTP or an IEEE 1588v2 clock; and before identifying the data packet
to which the delay measurement flag is added, performing, by the
downstream TLP, time synchronization with the DCP managing the
downstream TLP by using the NTP or an IEEE 1588v2 clock;
the adding a delay measurement flag to a data packet of the service
flow, and acquiring data packet delay measurement information
corresponding to the delay measurement flag further includes:
adding, by the upstream TLP, a delay measurement flag to the data
packet of the target service flow, acquiring a measurement period
identifier corresponding to the delay measurement flag, so that
after acquiring the measurement period identifier, the DCP managing
the upstream TLP transmits information about the measurement period
identifier to the MCP; and
acquiring, by the downstream TLP, start time of each measurement
period within the measurement period, and when identifying, within
each measurement period, the data packet to which the delay
measurement flag is added, acquiring the measurement period
identifier corresponding to the delay measurement flag, so that
after acquiring the start time and the measurement period
identifier, the DCP managing the downstream TLP transmits
information about the measurement period identifier to the MCP.
Optionally, the method for measuring a network delay further
includes:
transmitting, by the upstream TLP, a measurement packet to the
downstream TLP, where the measurement packet includes: transmit-end
timestamp information; and
receiving, by a receiving module of the downstream TLP, the
measurement packet, generating arrival timestamp information of the
measurement packet, and transmitting the measurement packet and the
arrival timestamp information to the DCP managing the downstream
TLP, so that the DCP determines whether the arrival timestamp
information and receive-end timestamp information pertain to a
preset duration range, and if the arrival timestamp information and
the receive-end timestamp information pertain to the preset
duration range, determines that the transmit-end timestamp
information and the receive-end timestamp information pertain to a
same data packet and transmits a result of the determining to the
MCP.
Optionally, in the method for measuring a network delay, the
transmit-end delay measurement information further includes:
transmit-end service flow characteristic information and a
transmit-end fragment reassembly identifier; and the receive-end
delay measurement information further includes: receive-end service
flow characteristic information and a receive-end fragment
reassembly identifier;
so that the DCP managing the upstream TLP acquires the transmit-end
delay measurement information and transmits the transmit-end delay
measurement information to the MCP, and the DCP managing the
downstream TLP acquires the receive-end delay measurement
information and transmits the receive-end delay measurement
information to the MCP; therefore, the MCP determines, according to
the transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, that the transmit-end timestamp
information and the receive-end timestamp information are timestamp
information corresponding to a same data packet.
Optionally, in the method for measuring a network delay, the
adding, by an upstream TLP, a delay measurement flag to the data
packet of the target service flow includes:
adding the delay measurement flag in a reserved bit of TOS or a
reserved bit of Flags in an IP header of the data packet.
Optionally, in the method for measuring a network delay, the
identifying a service flow according to service flow characteristic
information includes:
identifying the service flow according to information about at
least two tuples in a quintuple.
According to still another aspect, an embodiment of the present
application provides a method for measuring a network delay,
including:
receiving transmit-end delay measurement information transmitted by
a DCP corresponding to an upstream TLP and receive-end delay
measurement information transmitted by a DCP corresponding to a
downstream TLP, where the transmit-end delay measurement
information includes: transmit-end timestamp information, a service
flow identifier, and a TLP identifier; and the receive-end delay
measurement information includes: receive-end timestamp
information, a service flow identifier, and a TLP identifier;
and
determining details about a single network delay according to the
transmit-end delay measurement information and the receive-end
delay measurement information.
Optionally, the method for measuring a network delay further
includes:
receiving, by an MCP, a measurement period identifier transmitted
by the DCP managing the upstream TLP, receiving, by the MCP, a
measurement period identifier transmitted by the DCP managing the
downstream TLP, determining, by the MCP according to the
measurement period identifier transmitted by the DCP managing the
upstream TLP and the measurement period identifier transmitted by
the DCP managing the downstream TLP, whether the transmit-end delay
measurement information and the receive-end delay measurement
information pertain to a same measurement period, and if the
transmit-end delay measurement information and the receive-end
delay measurement information pertain to a same measurement period,
determining, by the MCP, the details about a single network delay
according to the transmit-end delay measurement information and the
receive-end delay measurement information.
Optionally, the method for measuring a network delay further
includes:
receiving, by an MCP, the transmit-end delay measurement
information transmitted by the DCP corresponding to the upstream
TLP, receiving, by the MCP, the receive-end delay measurement
information that is determined as pertaining to a same data packet
as the transmit-end delay measurement information and is
transmitted by the DCP corresponding to the downstream TLP,
determining, by the MCP, the details about a single network delay
according to the transmit-end delay measurement information and the
receive-end delay measurement information.
Optionally, the method for measuring a network delay further
includes:
receiving, by an MCP, the transmit-end delay measurement
information transmitted by the DCP corresponding to the upstream
TLP, where the transmit-end delay measurement information includes:
the timestamp information, the service flow identifier, the TLP
identifier, transmit-end service flow characteristic information,
and a transmit-end fragment reassembly identifier;
receiving, by the MCP, the receive-end delay measurement
information transmitted by the DCP corresponding to the downstream
TLP, where the receive-end delay measurement information includes:
the timestamp information, the service flow identifier, the TLP
identifier, receive-end service flow characteristic information,
and a receive-end fragment reassembly identifier; and
determining, by the MCP according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier,
whether the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same data packet; and if the transmit-end timestamp information and
the receive-end timestamp information are timestamp information
corresponding to a same data packet, determining, by the MCP, the
details about a single network delay according to the transmit-end
delay measurement information and the receive-end delay measurement
information.
According to one aspect, an embodiment of the present application
provides a DCP, including:
an acquiring module, configured to acquire delay measurement
information obtained by measuring a service flow by at least one
TLP, where the delay measurement information includes: timestamp
information, a service flow identifier, and a TLP identifier;
and
a transmitting module, configured to transmit the delay measurement
information to a measurement control point MCP, so that the MCP
determines details about a network delay according to the timestamp
information, the service flow identifier, and the TLP
identifier.
Optionally, the DCP is a DCP managing an upstream TLP; and
the acquiring module is specifically configured to acquire
transmit-end delay measurement information obtained by measuring a
transmitted service flow by at least one upstream TLP;
or,
the DCP is a DCP managing a downstream TLP; and
the acquiring module is specifically configured to acquire
receive-end delay measurement information obtained by measuring a
received service flow by at least one downstream TLP;
the transmitting, by the DCP, the delay measurement information to
an MCP includes:
the DCP is a DCP managing an upstream TLP; and
the transmitting module is specifically configured to transmit the
transmit-end delay measurement information to the MCP, where the
transmit-end delay measurement information includes: transmit-end
timestamp information, a service flow identifier, and a TLP
identifier;
or,
the DCP is a DCP managing a downstream TLP; and
the transmitting module is specifically configured to transmit the
receive-end delay measurement information to the MCP, where the
receive-end delay measurement information includes: receive-end
timestamp information, a service flow identifier, and a TLP
identifier.
Optionally, in the DCP, the acquiring module includes:
a first acquiring unit, configured to acquire the transmit-end
delay measurement information obtained by measuring the transmitted
service flow by the at least one upstream TLP, or acquire the
receive-end delay measurement information obtained by measuring the
received service flow by the at least one downstream TLP; and
a period identifier acquiring unit, configured to: when a
measurement period ends, the DCP managing the upstream TLP acquires
a measurement period identifier, and transmits the measurement
period identifier to the MCP; or when a measurement period of the
DCP managing the downstream TLP starts, the period identifier
acquiring unit acquires start time of the measurement period, where
if a difference between the start time and the timestamp
information is less than or equal to a preset duration, the
receive-end delay measurement information pertains to measurement
information corresponding to the measurement period identifier; and
if the difference between the start time and the timestamp
information is greater than the preset duration, the measurement
period identifier is increased by 1, the timestamp information
pertains to a next measurement period, and a measurement period
identifier of the DCP managing the downstream TLP within the
measurement period is acquired;
the transmitting module includes:
a first transmitting unit, configured to transmit the transmit-end
delay measurement information to the MCP, or transmit the
receive-end delay measurement information to the MCP; and
a second transmitting unit, configured to: when the measurement
period ends, transmit to the MCP the measurement period identifier
acquired by the period identifier acquiring unit of the DCP
managing the upstream TLP, or transmit to the MCP the measurement
period identifier acquired by the period identifier acquiring unit
of the DCP managing the downstream TLP.
Optionally, in the DCP, the preset duration is 2/3 of a duration of
the measurement period.
Optionally, the DCP further includes:
a time synchronization module, configured to: before the acquiring
module acquires the delay measurement information obtained by the
at least one TLP by measuring the service flow, perform time
synchronization with the TLP by using the NTP or an IEEE 1588v2
clock, and perform time synchronization between the DCP managing
the upstream TLP and the DCP managing the downstream TLP by using
the NTP or an IEEE 1588v2 clock.
Optionally, in the DCP, the acquiring module includes:
a second acquiring unit, configured to acquire the transmit-end
delay measurement information obtained by measuring the transmitted
service flow by the at least one upstream TLP, or acquire the
receive-end delay measurement information obtained by measuring the
received service flow by the at least one downstream TLP; and
a measurement packet acquiring unit, configured to acquire a
measurement packet transmitted by the upstream TLP and received by
the at least one downstream TLP, and arrival timestamp information
of the measurement packet, which is generated when the measurement
packet arrives at the downstream TLP, where the measurement packet
includes: transmit-end timestamp information;
the determining module is specifically configured to determine
whether the arrival timestamp information and the receive-end
timestamp information pertain to a preset duration range; and if
the arrival timestamp information and the receive-end timestamp
information pertain to the preset duration range, determine that
the transmit-end timestamp information and the receive-end
timestamp information pertain to a same data packet;
the transmitting module is specifically configured to transmit a
result of the determining to the MCP.
Optionally, the DCP is a data collecting point managing an upstream
TLP;
the acquiring module is specifically configured to acquire the
transmit-end delay measurement information, where the transmit-end
delay measurement information further includes: transmit-end
service flow characteristic information and a transmit-end fragment
reassembly identifier; and
the transmitting module is specifically configured to transmit the
transmit-end delay measurement information to the MCP; or
the DCP is a data collecting point managing a downstream TLP;
the acquiring module is specifically configured to acquire the
receive-end delay measurement information, where the receive-end
delay measurement information further includes: receive-end service
flow characteristic information and a receive-end fragment
reassembly identifier; and
the transmitting module is specifically configured to transmit the
receive-end delay measurement information to the MCP, so that the
MCP determines, according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier,
that the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same service flow.
According to another aspect, an embodiment of the present
application provides a TLP, including:
an identifying module, configured to identify a service flow
according to service flow characteristic information, and determine
whether the service flow is a target service flow;
a timestamp acquiring module, configured to: if the service flow is
the target service flow, add a delay measurement flag to a data
packet of the service flow, and acquire data packet delay
measurement information corresponding to the delay measurement
flag; and
a determining module, configured to determine delay measurement
information, where the delay measurement information includes:
timestamp information, a service flow identifier, a TLP identifier,
so that after acquiring the delay measurement information, the DCP
transmits the delay measurement information to an MCP.
Optionally, in the TLP, the adding a delay measurement flag to a
data packet of the service flow, and acquiring data packet delay
measurement information corresponding to the delay measurement flag
by the timestamp acquiring module includes:
a timestamp acquiring module of an upstream TLP is specifically
configured to add a delay measurement flag to the data packet of
the target service flow, and acquire transmit-end delay measurement
information of the data packet corresponding to the delay
measurement flag, where the transmit-end delay measurement
information includes: transmit-end timestamp information, a service
flow identifier, and a TLP identifier, so that after acquiring the
transmit-end delay measurement information, a DCP managing the
upstream TLP transmits the transmit-end delay measurement
information to the MCP; and
a timestamp acquiring module of a downstream TLP is specifically
configured to: when the identifying module identifies the data
packet to which the delay measurement flag is added, acquire
receive-end delay measurement information of the data packet
corresponding to the delay measurement flag, where the receive-end
delay measurement information includes: receive-end timestamp
information, a service flow identifier, and a TLP identifier, so
that after acquiring the receive-end delay measurement information,
a DCP managing the downstream TLP transmits the receive-end delay
measurement information to the MCP.
Optionally, the TLP is an upstream TLP; the TLP further
includes:
a time synchronization module, specifically configured to: before
the timestamp acquiring module of the upstream TLP adds the delay
measurement flag to the data packet of the target service flow,
perform time synchronization with the DCP managing the upstream TLP
by using the NTP or an IEEE 1588v2 clock; or
the TLP is a downstream TLP, and the time synchronization module is
specifically configured to: before the identifying module of the
downstream TLP identifies the data packet to which the delay
measurement flag is added, perform time synchronization with the
DCP managing the downstream TLP by using the NTP or an IEEE 1588v2
clock; and
the TLP further includes
a measurement period identifier acquiring module, configured to:
acquire a measurement period identifier corresponding to the delay
measurement flag by using a measurement period identifier acquiring
module of the upstream TLP, so that after acquiring the measurement
period identifier, the DCP managing the upstream TLP transmits the
measurement period identifier to the MCP; and acquire the
measurement period identifier corresponding to the delay
measurement flag and start time of each measurement period by using
a measurement period identifier acquiring module of the downstream
TLP, so that after acquiring the start time and the measurement
period identifier, the DCP managing the downstream TLP performs
matching between the start time and the measurement period
identifier, and then transmits the measurement period identifier to
the MCP.
Optionally, the TLP further includes:
a transmitting module, specifically configured to transmit a
measurement packet to the downstream TLP by using a transmitting
module of the upstream TLP, where the measurement packet includes:
transmit-end timestamp information; and
a receiving module, specifically configured to: acquire the
measurement packet by using a receiving module of the downstream
TLP, generate arrival timestamp information of the measurement
packet, and transmit the measurement packet and the arrival
timestamp information to the DCP managing the downstream TLP, so
that the DCP determines whether the arrival timestamp information
and receive-end timestamp information pertain to a preset duration
range, and if the arrival timestamp information and the receive-end
timestamp information pertain to the preset duration range,
determines that the transmit-end timestamp information and the
receive-end timestamp information pertain to a same data packet and
transmits a result of the determining to the MCP.
Optionally, in the TLP, the transmit-end delay measurement
information acquired by the timestamp acquiring module of the
upstream TLP further includes: transmit-end service flow
characteristic information and a transmit-end fragment reassembly
identifier; and the receive-end delay measurement information
acquired by the timestamp acquiring module of the downstream TLP
further includes: receive-end service flow characteristic
information and a receive-end fragment reassembly identifier;
so that the DCP managing the upstream TLP acquires the transmit-end
delay measurement information and transmits the transmit-end delay
measurement information to the MCP, and the DCP managing the
downstream TLP acquires the receive-end delay measurement
information and transmits the receive-end delay measurement
information to the MCP; therefore, the MCP determines, according to
the transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, that the transmit-end timestamp
information and the receive-end timestamp information are timestamp
information corresponding to a same service flow.
Optionally, in the TLP, the adding, by the timestamp acquiring
module of the upstream TLP, a delay measurement flag to the data
packet of the target service flow includes:
adding, by the timestamp acquiring module, a delay measurement flag
in a reserved bit of TOS or a reserved bit of Flags in an IP header
of the data packet.
Optionally, in the TLP, the identifying module is specifically
configured to identify the service flow according to information
about at least two tuples in a quintuple.
According to still another aspect, an embodiment of the present
application provides an MCP, including:
a receiving module, configured to receive transmit-end delay
measurement information transmitted by a DCP corresponding to an
upstream TLP and receive-end delay measurement information
transmitted by a DCP corresponding to a downstream TLP, where the
transmit-end delay measurement information includes: transmit-end
timestamp information, a service flow identifier, and a TLP
identifier; and the receive-end delay measurement information
includes: receive-end timestamp information, a service flow
identifier, and a TLP identifier; and
a determining module, configured to determine details about a
single network delay according to the transmit-end delay
measurement information and the receive-end delay measurement
information.
Optionally, the MCP further includes:
a time synchronization module, configured to perform
synchronization with the DCP by using the NTP or an IEEE 1588v2
clock;
the receiving module includes:
a first receiving unit, configured to receive the transmit-end
delay measurement information transmitted by the DCP corresponding
to the upstream TLP and the receive-end delay measurement
information transmitted by the DCP corresponding to the downstream
TLP, where the transmit-end delay measurement information includes:
transmit-end timestamp information, a service flow identifier, and
a TLP identifier; and the receive-end delay measurement information
includes: receive-end timestamp information, a service flow
identifier, and a TLP identifier; and
a second receiving unit, configured to receive a measurement period
identifier transmitted by the DCP managing the upstream TLP, and
receive a measurement period identifier transmitted by the DCP
managing the downstream TLP;
the determining module further includes:
a first matching unit, specifically configured to determine,
according to the measurement period identifier transmitted by the
DCP managing the upstream TLP and the measurement period identifier
transmitted by the DCP managing the downstream TLP, whether the
transmit-end delay measurement information and the receive-end
delay measurement information pertain to a same measurement period;
and
a determining module, specifically configured to: if the
transmit-end delay measurement information and the receive-end
delay measurement information pertain to a same measurement period,
determine the details about a single network delay according to the
transmit-end delay measurement information and the receive-end
delay measurement information.
Optionally, in the MCP, the receiving module is specifically
configured to receive the transmit-end delay measurement
information transmitted by the DCP corresponding to the upstream
TLP, and the receive-end delay measurement information that is
determined as pertaining to a same data packet as the transmit-end
delay measurement information and is transmitted by the DCP
corresponding to the downstream TLP; and
the determining module is specifically configured to determine the
details about a single network delay according to the transmit-end
delay measurement information and the receive-end delay measurement
information.
Optionally, in the MCP, the receiving module is specifically
configured to: receive the transmit-end delay measurement
information transmitted by the DCP corresponding to the upstream
TLP, where the transmit-end delay measurement information includes:
the timestamp information, the service flow identifier, the TLP
identifier, transmit-end service flow characteristic information,
and a transmit-end fragment reassembly identifier; and receive the
receive-end delay measurement information transmitted by the DCP
corresponding to the downstream TLP, where the receive-end delay
measurement information includes: the timestamp information, the
service flow identifier, the TLP identifier, receive-end service
flow characteristic information, and a receive-end fragment
reassembly identifier; and
the determining module includes:
a second matching unit, configured to determine, according to the
transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, whether the transmit-end timestamp
information and the receive-end timestamp information are timestamp
information corresponding to a same service flow; and
a determining unit, specifically configured to: if the transmit-end
timestamp information and the receive-end timestamp information are
timestamp information corresponding to a same service flow,
determine the details about a single network delay according to the
transmit-end delay measurement information and the receive-end
delay measurement information.
An embodiment of the present application provides a system for
measuring a network delay, including: the foregoing DCP, the
foregoing TLP, and the foregoing MCP.
With the method, the apparatus, and the system for measuring a
network delay according to the embodiments of the present
application, a DCP acquires delay measurement information obtained
by directly measuring a service flow by at least one TLP, and
transmits the delay measurement information to an MCP uniformly, so
that the MCP determines details about a network delay according to
related information in the delay measurement information, thereby
implementing direct delay measurement of the service flow.
BRIEF DESCRIPTION OF DRAWINGS
To describe the technical solutions in the embodiments of the
present application more clearly, the following briefly introduces
the accompanying drawings required for describing the embodiments.
Apparently, the accompanying drawings in the following description
show merely some embodiments of the present application, and a
person of ordinary skill in the art may still derive other drawings
from these accompanying drawings without creative efforts.
FIG. 1 is a flowchart of Embodiment 1 of a method for measuring a
network delay according to the present application;
FIG. 2 is a schematic flowchart of implementation of Embodiment 3
of a method for measuring a network delay according to the present
application;
FIG. 3 is a schematic flowchart of implementation of Embodiment 4
of a method for measuring a network delay according to the present
application;
FIG. 4 is a schematic flowchart of implementation of Embodiment 5
of a method for measuring a network delay according to the present
application;
FIG. 5 is a flowchart of Embodiment 6 of a method for measuring a
network delay according to the present application;
FIG. 6 is a flowchart of Embodiment 11 of a method for measuring a
network delay according to the present application;
FIG. 7 is a schematic diagram of two-way delay measurement in
Embodiment 12 of a method for measuring a network delay according
to the present application;
FIG. 8 is a schematic structural diagram of Embodiment 1 of a DCP
according to the present application;
FIG. 9 is a schematic structural diagram of Embodiment 2 of a DCP
according to the present application;
FIG. 10 is a schematic structural diagram of Embodiment 3 of a DCP
according to the present application;
FIG. 11 is a schematic structure view of Embodiment 1 of a TLP
according to the present application;
FIG. 12 is a schematic structural diagram of Embodiment 2 of a TLP
according to the present application;
FIG. 13 is a schematic structural diagram of Embodiment 3 of a TLP
according to the present application;
FIG. 14 is a schematic structural diagram of Embodiment 1 of an MCP
according to the present application;
FIG. 15 is a schematic structural diagram of Embodiment 2 of an MCP
according to the present application;
FIG. 16 is a schematic structural diagram of Embodiment 4 of an MCP
according to the present application;
FIG. 17 is a schematic structural diagram of Embodiment 1 of a
system for measuring a network delay according to the present
application; and
FIG. 18 is a schematic diagram of Embodiment 2 of a system for
measuring a network delay according to the present application.
DESCRIPTION OF EMBODIMENTS
To make the objectives, technical solutions, and advantages of the
embodiments of the present application clearer, the following
clearly describes the technical solutions in the embodiments of the
present application with reference to the accompanying drawings in
the embodiments of the present application. Apparently, the
described embodiments are a part rather than all of the embodiments
of the present application. All other embodiments obtained by a
person of ordinary skill in the art based on the embodiments of the
present application without creative efforts shall fall within the
protection scope of the present application.
FIG. 1 is a flowchart of Embodiment 1 of a method for measuring a
network delay according to the present application. As illustrated
in FIG. 1, the method according to this embodiment may include:
S100. Acquire delay measurement information obtained by measuring a
service flow by at least one target logical port (TLP).
Specifically, the delay measurement information includes: timestamp
information, a service flow identifier, and a TLP identifier.
A data collecting point (Data Collecting Point, hereinafter
referred to as DCP) acquires delay measurement information obtained
by measuring a service flow by at least one target logical port
(Target Logical Port, hereinafter referred to as TLP). The TLP
corresponds to an upstream transmit-end ingress of a network or a
downstream receive-end egress of a network. DCPs corresponding to
the TLP are deployed on an upstream transmit device and a
downstream receive device, to read delay measurement information of
the TLP on the device each of the DCPs locates. That is, when the
TLP corresponds to an upstream transmit-end ingress of a network, a
DCP corresponding to the TLP is deployed on an upstream transmit
device corresponding to the upstream transmit-end ingress of the
network; and when the TLP corresponds to a downstream receive-end
egress of a network, a DCP corresponding to the TLP is deployed on
a downstream receiving device corresponding to the downstream
receive-end egress of the network.
When a service flow enters a network, a unique service flow
identifier is generated for the service flow correspondingly.
Optionally, a service flow ID may be used as an identifier of the
service flow. One service flow identifier uniquely corresponds to
one service flow. Therefore, when a scenario of point to multipoint
transmission or multipoint to multipoint transmission of the
service flow occurs on the network, that is, when the DCPs on the
upstream transmitting device and downstream receiving device
acquire delay measurement information obtained by measuring the
service flow by multiple TLPs, it may be determined, according to
the service flow identifier, whether related delay measurement
information pertains to a same service flow.
Each piece of delay measurement information includes a
corresponding TLP identifier. In this case, during acquisition of
the delay measurement information obtained by measuring the service
flow by the multiple TLPs, a measurement control point (Measurement
Control Point, hereinafter referred to as MCP) may differentiate
delay measurement information from different TLPs according to TLP
identifiers.
S102. Transmit the delay measurement information to a measurement
control point (MCP), so that the MCP determines details about a
network delay according to the timestamp information, the service
flow identifier, and the TLP identifier.
Specifically, a process of acquiring and transmitting the delay
measurement information by the DCP is implemented by a network
device-based management network. For each node device on the
network, in addition to a service port for transmitting a service
flow, a management port is also configured, the node devices may
form the management network through the management ports. In this
way, a transmission path of the delay measurement information may
be used for out-band transmission over the management network, or a
transmission path of the delay measurement information may be used
for in-band transmission along a same path as a transmission path
of a target service flow through the service port. Optionally, the
management network may employ a virtual private network (Virtual
Private Network, hereinafter referred to as VPN), a digital
communication network (Data Communication Network, hereinafter
referred to as DCN), or a public network with reachable IP.
With the method for measuring a network delay according to this
embodiment, a DCP acquires delay measurement information obtained
by measuring a service flow by at least one TLP, thereby
implementing direct measurement of the service flow; and the DCP
transmits the delay measurement information to an MCP uniformly, so
that the MCP determines details about a network delay according to
related information in the delay measurement information. In
addition, when multiple TLPs separately measure the service flow
and obtain respective data packet measurement information, the
delay measurement information is transmitted, so that the MCP
uniformly determines details about a delay of the service flow
according to the delay measurement information. In this way,
accurate delay measurement of a service flow is directly
implemented in a scenario of point to point transmission or point
to multipoint transmission on the network, and details about a real
delay of the service flow is reflected.
Based on Embodiment 1 of the method for measuring a network delay
according to the present application, in Embodiment 2 of the method
for measuring a network delay according to the present application,
the acquiring, by the DCP, delay measurement information obtained
by measuring a service flow by at least one TLP includes:
acquiring, by a data collecting point (DCP) managing an upstream
TLP, transmit-end delay measurement information obtained by
measuring a transmitted service flow by at least one upstream TLP;
and
acquiring, by a DCP managing a downstream TLP, receive-end delay
measurement information obtained by measuring a received service
flow by at least one downstream TLP.
The transmitting the delay measurement information to an MCP
includes:
transmitting, by the DCP managing the upstream TLP, the
transmit-end delay measurement information to the MCP, where the
transmit-end delay measurement information includes: transmit-end
timestamp information, a service flow identifier, and a TLP
identifier.
Specifically, according to this embodiment, DCPs are deployed at
upstream transmit ends, and the DCPs are used to manage TLPs at the
upstream transmit ends. After an upstream TLP identifies a
transmitted service flow and adds a delay measurement flag to a
data packet of the service flow, where a time point when the delay
measurement flag is added is transmit-end timestamp information,
the upstream TLP generates transmit-end delay measurement
information, and the DCPs acquire the transmit-end delay
measurement information of the upstream TLP. The transmit-end delay
measurement information includes: the transmit-end timestamp
information, the service flow identifier, and the TLP identifier
that are collected by at least one TLP at the upstream transmit
ends.
The transmitting the delay measurement information to an MCP
further includes:
transmitting, by the DCP managing the downstream TLP, the
receive-end delay measurement information to the MCP, where the
receive-end delay measurement information includes: receive-end
timestamp information, a service flow identifier, and a TLP
identifier.
Specifically, similar to the foregoing description, according to
this embodiment, DCPs are deployed at downstream receive ends, the
DCPs are used to manage TLPs at the downstream receive ends. First,
a downstream TLP identifies a service flow. If the service flow is
a target service flow, when identifying the data packet with the
delay measurement flag, the downstream TLP uses the time point as
receive-end timestamp information, and generates the receive-end
delay measurement information. A DCP acquires the receive-end delay
measurement information obtained by measuring a received service
flow by the downstream TLP. The receive-end delay measurement
information includes: the receive-end timestamp information, the
service flow identifier, and the TLP identifier that are collected
by at least one TLP at the downstream receive ends. It should be
noted that concepts of upstream and downstream are defined with
respect to a transmission direction of a service flow on the
network. With respect to different service flows, a same TLP may be
either an upstream TLP or a downstream TLP.
In one aspect, based on Embodiment 2 of the method for measuring a
network delay according to the present application, a method in
Embodiment 3 of the method for measuring a network delay according
to the present application further includes:
when a measurement period ends, acquiring, by the DCP managing the
upstream TLP, a measurement period identifier, and transmitting the
measurement period identifier to the MCP; and
acquiring, by the DCP managing the downstream TLP, start time of
the measurement period; where if a difference between the start
time and the timestamp information is less than or equal to a
preset duration, the receive-end delay measurement information
pertains to measurement information corresponding to the
measurement period identifier; and if the difference between the
start time and the timestamp information is greater than the preset
duration, the measurement period identifier is increased by 1, the
timestamp information pertains to a next measurement period, and
the measurement period identifier is transmitted to the MCP.
Optionally, the preset duration is 2/3 of a duration of the
measurement period.
Specifically, the measurement period identifier may be directly
acquired by the upstream TLP and the downstream TLP by using the
delay measurement information, alternatively, the measurement
period identifier may be acquired by the DCP managing the upstream
TLP and the DCP managing the downstream TLP according to the time
point when the transmit-end delay measurement information is
acquired and the time point when the receive-end delay measurement
information is acquired after the DCP managing the upstream TLP and
the DCP managing the downstream TLP read the transmit-end delay
measurement information and the receive-end delay measurement
information.
With respect to each measurement period, either a DCP or a TLP
corresponding to the DCP may generate a corresponding measurement
period identifier. The measurement period identifier may be
obtained through the DCP by using the following formula:
Measurement period identifier=Global quantity of seconds/Duration
of the measurement period
It should be noted that time synchronization is performed between
the upstream TLP and the DCP managing the upstream TLP, between the
downstream TLP and the DCP managing the downstream TLP, and between
the DCPs by using the Network Time Protocol (Network Time Protocol,
hereinafter referred to as NTP) or an IEEE 1588v2 clock; the global
quantity of seconds may be a time point when delay measurement
information is generated by a TLP, or may be a time point when a
DCP reads the delay measurement information; and the measurement
period identifier is an integer rounded from a result of dividing
the global quantity of seconds by the duration of the measurement
period. For example, assuming that the duration of each measurement
period is 1 s, when the time point when the upstream TLP adds a
delay measurement flag to a data packet within a measurement period
is 10 s, the measurement period identifier of the measurement
period is calculated according to the foregoing formula, that is,
10 s/1 s=10; assuming that the duration of each measurement period
is 2 s, when the time point when the upstream TLP adds a delay
measurement flag to a data packet within a measurement period is 7
s, 7/2=3.5, and the measurement period identifier is 3.
The upstream TLP takes the measurement period as a unit, and
selects a data packet in a service flow with each measurement
period and adds a delay measurement flag to the selected data
packet. Therefore, a measurement period identifier is generated for
each measurement period. For example, assuming that the upstream
TLP adds a delay measurement flag to a data packet A, the upstream
TLP generates transmit-end delay measurement information and
generates a corresponding measurement period identifier, where the
measurement period identifier is 10, to ensure that the MCP perform
delay calculation according to transmit-end timestamp information
and receive-end timestamp information that are corresponding to the
data packet A. When the measurement period ends, the DCP managing
the upstream TLP acquires the transmit-end timestamp information
and the measurement period identifier generated by the upstream
TLP, and transmits the transmit-end timestamp information and the
measurement period identifier (that is, 10) to the MCP. After the
data packet A is transmitted over the network and arrives at a
receive end, the downstream TLP identifies within a measurement
period the data packet A to which the delay measurement flag is
added, generates receive-end delay measurement information and a
measurement period identifier, and transmits the receive-end delay
measurement information and the measurement period identifier to
the DCP managing the downstream TLP. The DCP managing the
downstream TLP determines that the measurement period identifier is
10 if the difference between the start time and the timestamp
information is less than or equal to a preset duration, and
transmits the receive-end delay measurement information and the
measurement period identifier 10 to the MCP; and if the difference
between the start time and the timestamp information is greater
than the preset duration, the DCP increases the measurement period
identifier by 1, that is, the measurement period identifier is 11,
and then transmits the receive-end delay measurement information
and the new measurement period identifier 11 to the MCP. The MCP
associates, according to the measurement period identifier 11, the
receive-end delay measurement information with the transmit-end
delay measurement information with the measurement period
identifier 11 that is transmitted by the DCP managing the upstream
TLP.
Optionally, to ensure that the upstream TLP and the downstream TLP
generate the measurement period identifier based on a same time,
the DCP managing the upstream TLP performs time synchronization
with the upstream TLP by using the NTP or the IEEE 1588 v2 clock,
and the DCP managing the downstream TLP performs time
synchronization with the downstream TLP by using the NTP or an IEEE
1588v2 clock. In addition, the DCP managing the upstream TLP also
performs time synchronization with the DCP managing the downstream
TLP by using the NTP or an IEEE 1588v2 clock.
Specifically, the Network Time Protocol (Network Time Protocol,
hereinafter referred to as NTP) and an IEEE 1588v2 clock are both
external synchronization tools. The NTP is a commonly used network
synchronization tool. A synchronization deviation of the NTP is 1
ms to 50 ms, and the NTP is capable of meeting synchronization
requirements of the method for measuring a network delay according
to this embodiment. An IEEE 1588v2 clock is a high-precision clock
by using the IEEE 1588v2 protocol. The time synchronization method
involved in the present application calibrates local time of the
upstream TLP and the DCP managing the upstream TLP, local time of
the downstream TLP and the DCP managing the downstream TLP, and
local time between the DCP managing the upstream TLP and the DCP
managing the downstream TLP based on a common time reference (the
NTP or an IEEE 1588v2 clock). Optionally, boundary points (start
time points of various periods) of various periods are defined by
using the NTP or an IEEE 1588v2 clock, that is, a start time point
of each measurement period of the upstream TLP and the DCP managing
the upstream TLP are aligned with a start time point of each
measurement period of the downstream TLP and the DCP managing the
downstream TLP. With respect to a network in which an IEEE 1588v2
clock has been deployed, the method for measuring a network delay
according to this embodiment optionally employs the IEEE 1588v2
clock to perform time synchronization.
FIG. 2 is a schematic flowchart of implementation of Embodiment 3
of a method for measuring a network delay according to the present
application. With reference to FIG. 2, the following describes in
detail the method for measuring a network delay according to
Embodiment 3 of the present application.
As illustrated in FIGS. 2, R1 and R2 are network node devices, TLPs
and corresponding DCPs are deployed on R1 and R2, and an MCP is
deployed on any network node device on the network. Optionally, the
MCP is deployed on a node device with powerful functions. Referring
to FIG. 2, with respect to R1 and R2, two service flows that are in
opposite directions may be used for delay measurement.
Considering that R1 and R2 both have its local time, and
corresponding time axes are respectively a local time of R1 and a
local time of R2, time and period synchronization is achieved
between R1 and R2 by using an external time synchronization tool or
the like. T[N] and T[N+1] represent respective measurement period
identifiers corresponding to internals of two neighboring
measurement periods.
As can be seen from FIG. 2, the two time axes of the local times of
R1 and R2 and boundary points of the measurement periods such as
T[N] and T[N+1] are basically aligned by using the NTP or an IEEE
1588v2 clock. A deviation of the two local time axes is caused by
an error of the network itself, or precision of the NTP or the IEEE
1588v2 clock.
Within a measurement period T[N] with a same measurement period
identifier at two ends of R1 and R2, at the TLPs at transmit ends
and receive ends of R1 and R2, when the measurement period
(including a range of the first T/n of the measurement period)
starts, one-way delay measurement is oppositely initiated for a
data packet of a service flow. Within each measurement period, a
delay measurement flag is added to a data packet in only one target
service flow.
At the upstream transmit ends of R1 and R2, the TLPs add a delay
measurement flag to a data packet, and obtains local transmit
timestamps t1 and t3. At the downstream receive ends of R1 and R2,
within the corresponding measurement period T[N], the TLPs detects
a data packet with the delay measurement flag. In this case, the
downstream TLPs may acquire local receive timestamps t2 and t4, and
a TLP may report delay measurement information containing timestamp
information to a DCP managing the TLP; or when each measurement
period ends, the DCPs managing the TLPs read the delay measurement
information.
All the delay measurement information includes: timestamp
information, a service flow identifier, and a TLP identifier, and
carries the same period identifier T[N], where the service flow
identifier and the TLP identifier reflect information in a receive
or transmit direction. The delay measurement information is read by
the DCP and then transmitted by the DCP to the MCP, and the MCP
performs matching and calculation according to T[N].
A two-way delay may be taken as a sum of two one-way delays, as
represented by the following formula: Two-way
delay=(t2-t1)+(t4-t3)=(t4-t1)-(t3-t2)
This formula also indicates that two times of one-way delays
measurement do not necessarily require coupling of a time sequence.
Therefore, two one-way delays measurements may be separately
initiated and performed.
If precise time synchronization is deployed on the network, one-way
delay 1 d(R1.fwdarw.R2)=t2-t1, 1 d(R2.fwdarw.R1)=t4-t3. With
respect to selection of a measurement period T, assuming that the
measurement period is T, a sum of a transmission delay and an
out-of-order delay of a service flow is D, and a synchronization
error between measurement periods of a transmit end and a receive
end is A, then the measurement period T satisfies the following two
conditions: 1. (2*.DELTA.-D)<T/3; 2. (2*.DELTA.+D)<2*T/3.
With respect to period pertaining rules of the measurement period
identifier and the receive-end timestamp information, assuming that
a transmit-end timestamp within the N.sup.th period is TX, if a
service flow exists within 100 ms starting from start time of each
measurement period, then a delay measurement flag is added to the
first data packet of the service flow, and an upstream TLP records
a timestamp Time_TX[N] at that time, and acquires a measurement
period identifier N; otherwise, a delay measurement packet is not
marked within this period.
With respect to determining of the measurement period to which a
receive end pertains, assuming that within the N.sup.th period, the
receive end receives a data packet to which a delay measurement
flag is added, a downstream TLP records a local timestamp Time_Rx.
If the downstream TLP acquires the Time_Rx when the period ends, a
DCP managing the downstream TLP performs the following
calculation:
Time_RX-Time[N] (Time[N] is start time of the current period. The
DCP performs synchronization with the managed TLP by using the NTP
or an IEEE 1588v2 clock. Therefore, the DCP may directly acquire
the start time of the period on the local time of the DCP).
If a calculation result is greater than 2T/3 (T is a duration of
the period), the timestamp pertains to a next period (the
measurement period identifier is increased by 1 because a data
packet arrives ahead of time due to a synchronization error);
otherwise, the timestamp information pertains to the current
period.
If reading is performed at 2T/3 of the period, an obtained Time_RX
is a receive timestamp Time_RX[N] of the period N.
If .DELTA.<100 ms, and the transmission delay plus the
out-of-order delay D is less than 200 ms, the selected delay
measurement period T is greater than 1 s.
With the method for measuring a network delay according to this
embodiment of the present application, when a measurement period
ends, a DCP managing an upstream TLP acquires a measurement period
identifier and transmit-end delay measurement information, and
transmits the measurement period identifier to an MCP; a DCP of a
downstream TLP acquires a measurement period identifier and
receive-end delay measurement information, and the DCP determines
the acquired measurement period identifier, and transmits the
determined measurement period identifier and the receive-end delay
measurement information to the MCP, so that the MCP associates,
according to an upstream measurement period identifier and a
downstream measurement period identifier, the transmit-end delay
measurement information and the receive-end delay measurement
information that pertain to a same period of a same service flow,
thereby directly and accurately measuring details about a delay of
a service flow.
In another aspect, based on Embodiment 2 of the method for
measuring a network delay according to the present application, a
method for measuring a network delay according to Embodiment 4 of
the present application further includes:
acquiring, by the DCP managing the downstream TLP, a measurement
packet transmitted by the upstream TLP and received by the at least
one downstream TLP, and arrival timestamp information of the
measurement packet, which is generated when the measurement packet
arrives at the downstream TLP, where the measurement packet
includes: transmit-end timestamp information.
Specifically, with respect to a network in which network
receive-end and network transmit-end devices, a delay of a service
flow is measured by taking a measurement period as a unit, but a
receive-end measurement period and a transmit-end measurement
period do not pass a network for performing time synchronization by
using a time synchronization tool, the upstream TLP adds a delay
measurement flag to one data packet within each measurement period,
and generates transmit-end delay measurement information, where the
transmit-end measurement information includes timestamp
information, a service flow identifier, and a TLP identifier. The
upstream TLP transmits a measurement packet including transmit-end
timestamp information to the downstream TLP at the receive end. The
DCP managing the downstream TLP compares arrival timestamp
information of the measurement packet with the receive-end delay
measurement information, to ensure that the transmit-end delay
measurement information and the receive-end delay measurement
information pertain to a same measurement period.
The DCP managing the downstream TLP performs matching and
identification to determine whether the arrival timestamp
information and the receive-end timestamp information pertain to a
preset duration range; if the arrival timestamp information and the
receive-end timestamp information pertain to the preset duration
range, the DCP managing the downstream TLP determines that the
transmit-end timestamp information in the measurement packet and
the receive-end timestamp information generated by the downstream
TLP pertain to a same measurement period, that is, pertaining to a
same data packet (because within each period, a delay measurement
flag is added to only one data packet), and transmits a result of
the determining to the MCP.
Optionally, the DCP managing the downstream TLP may transmit the
transmit-end timestamp information and the receive-end timestamp
information that pertain to a same measurement period to the MCP,
and the MCP performs calculation. Alternatively, the DCP may
directly determine details about a data packet delay within the
period according to the transmit-end timestamp information and the
receive-end timestamp information that pertain to a same
measurement period, and then transmits calculated details about the
delay to the MCP.
Specifically, FIG. 3 is a schematic flowchart of implementation of
Embodiment 4 of a method for measuring a network delay according to
the present application. As illustrated in FIG. 3, when a data
packet to which a delay measurement flag is added is transmitted
over a network and arrives at a receive end, there is a delay Ds;
and when a measurement packet carrying transmit-end timestamp
information and transmitted by an upstream TLP arrives at the
receive end, there is also a delay Dc. A delay difference is
defined by using the following formula: Delay difference
.DELTA.=|Ds-Dc|.
Referring to FIG. 3, assuming that each of measurement periods of
an upstream TLP of a transmit end and a downstream TLP of a receive
end is T, the upstream TLP of the transmit end (TX) adds a delay
measurement flag to a data packet A of a service flow at time t1,
to obtain local transmit-end timestamp information t1, generates a
measurement packet including the transmit-end timestamp information
t1, and transmits the measurement packet to the downstream TLP of
the receive end (RX). After a delay Ds, due to possible disorder,
the data packet A may arrive first, or the measurement packet may
arrive first. When the data packet A arrives at the downstream TLP
of the receive end first, the downstream TLP of the receive end
obtains receive-end timestamp information t2 of the service flow.
After a delay Dc, the measurement packet carrying t1 arrives at the
receive end; the receive end obtains arrival timestamp information
tc of the measurement packet. When the measurement packet arrives
at the downstream TLP first, the same principle applies.
For the matching and identification, the DCP managing the
downstream TLP sets |tc-t2|<delay difference .DELTA.; and during
an interval period T for measuring the delay, a delay measurement
flag is added to a data packet of the service flow only at the
beginning of a measurement period when Tdelay difference .DELTA..
Therefore, the DCP managing the downstream TLP performs matching
and identification as follows:
During a single measurement, the DCP managing the downstream TLP
first acquires the receive-end timestamp information t2, and takes
the receive-end timestamp information t2 as a reference. In a time
range of t2 plus delay difference .DELTA. or t2 minus delay
difference .DELTA., the DCP managing the downstream TLP acquires
the measurement packet at time tc, and then the transmit-end
timestamp information t1 may match the receive-end timestamp
information t2; that is, the transmit-end timestamp information and
the receive-end timestamp information pertain to a same data packet
within a same measurement period. Alternatively, the DCP managing
the downstream TLP first acquires the measurement packet, and takes
the arrival timestamp information tc of the measurement packet as a
reference. In a time frame of tc plus delay difference .DELTA. or
tc minus delay difference .DELTA., the DCP managing the downstream
TLP acquires the receive-end timestamp information t2, and then the
transmit-end timestamp information t1 may match the receive-end
timestamp information t2; that is, the transmit-end timestamp
information and the receive-end timestamp information pertain to a
same data packet within a same measurement period.
During a periodic measurement, during each periodic interval for
measuring a delay (the time interval during which the upstream TLP
adds a delay measurement flag to the data packet of the service
flow is T), the upstream TLP adds the delay measurement flag only
to one data packet of the service flow. On an actual network,
jitter of Ds and Dc occurs and Ds and Dc are prolonged, but the
jitter and prolonging are limited, there is a maximum value of the
delay difference .DELTA., that is, .DELTA. (MAX). As long as the
measurement period interval T>2.times..DELTA.(MAX)+minimum safe
time interval, it may be determined that during each sampling
interval, the t2 timestamp matches the protocol packet
corresponding to the t1.
Assuming that on the network, .DELTA. (MAX)=500 ms, considering 100
ms safe processing time, then T>2.times.500+100=1.1 S, and a
periodic measurement may be implemented.
With the method for measuring a network delay according to this
embodiment of the present application, a DCP managing a downstream
TLP acquires a measurement packet that is transmitted by an
upstream TLP and received by at least one downstream TLP; the DCP
managing the downstream TLP performs matching and identification to
determine whether transmit-end timestamp information and
receive-end timestamp information pertain to a preset duration
range; and if the transmit-end timestamp information and the
receive-end timestamp information pertain to the preset duration
range, the DCP managing the downstream TLP determines that the
transmit-end timestamp information and the receive-end timestamp
information pertain to a same measurement period, and transmits a
result of the determining to an MCP, thereby implementing direct
and accurate measurement of details about a delay of a service
flow.
In still another aspect, based on Embodiment 2 of the method for
measuring a network delay according to the present application, in
a method for measuring a network delay according to Embodiment 5 of
the present application, the transmit-end delay measurement
information further includes: transmit-end service flow
characteristic information and a transmit-end fragment reassembly
identifier; and the receive-end delay measurement information
further includes: receive-end service flow characteristic
information and a receive-end fragment reassembly identifier, so
that the MCP determines, according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier,
that the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same service flow.
Specifically, during a process for measuring a delay of a service
flow, it is critical to determine that transmit-end timestamp
information and receive-end timestamp information are acquired
respectively at a transmit end and a receive end of a network from
a same data packet that is in the service flow and to which a delay
measurement flag is added, there is a delay that the data packet
goes from the transmit-end to the receive-end of the network. With
respect to a data packet of the service flow, service
characteristic information and a fragment reassembly identifier
included in the data packet may uniquely identify the data packet.
The service flow characteristic information is a quintuple in an IP
header and information in a type of service TOS (Type of Service,
hereinafter referred to as TOS), where the quintuple refers to a
source IP address, a destination IP address, a protocol type, a
source protocol port number, and a destination protocol port number
in the IP header. During a transmission process of the data packet,
an oversized data packet is always divided into multiple sub-data
packets and then the sub-data packets are transmitted. With respect
to a fragmented data packet, a fragment reassembly identifier
pertaining to each sub-data packet is the same. After receiving the
fragmented sub-data packets, the receive end may reassemble the
sub-data packets into the original data packet according to the
fragment reassembly identifiers of the sub-data packets.
Accordingly, when a service flow is identified by the upstream TLP,
the upstream TLP adds a delay measurement flag to a data packet A
of the service flow, and generates transmit-end delay measurement
information, which includes transmit-end timestamp information, a
service flow identifier, a TLP identifier, transmit-end service
flow characteristic information, and a transmit-end fragment
reassembly identifier. The DCP managing the upstream TLP acquires
the transmit-end delay measurement information, and transmits the
transmit-end delay measurement information to the MCP. When the
downstream TLP identifies the data packet A with the delay
measurement flag, the downstream TLP generates receive-end delay
measurement information, which includes receive-end timestamp
information, a service flow identifier, a TLP identifier,
receive-end service flow characteristic information, and a
receive-end fragment reassembly identifier, and the DCP managing
the downstream TLP acquires the receive-end delay measurement
information, and transmits the receive-end delay measurement
information to the MCP. The MCP may determine, according to the
transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, that the transmit-end timestamp
information and the receive-end timestamp information are
respectively acquired by the transmit end and the receive end of
the network after a same data packet that is in the service flow
and to which a delay measurement flag is added is transmitted,
there is a delay that the data packet goes from the transmit-end to
the receive-end of the network, that is, matching between the
transmit-end delay measurement information and the receive-end
delay measurement information is implemented. Therefore, the MCP
performs delay measurement according to the successfully matched
transmit-end delay measurement information and receive-end delay
measurement information.
FIG. 4 is a schematic flowchart of implementation of Embodiment 5
of a method for measuring a network delay according to the present
application. With reference to FIG. 4, the following describes in
detail the method for measuring a network delay according to
Embodiment 5 of the present application.
During delay measurement, it is critical to determine that
transmit-end timestamp information and receive-end timestamp
information are acquired when a same data packet that is in a
service flow and to which a delay measurement flag is added passes
a network. In this embodiment, a quintuple of a data packet (a
source IP address, a destination IP address, a protocol type, a
source protocol port number, and a destination protocol port
number) and a fragment reassembly identifier (a fragment reassembly
ID) are used to perform matching. A matching principle of
Embodiment 5 of the method for measuring a network delay according
to the present application is as follows:
On an IP network, for a same VPN (on one VPN, a data packet has
non-overlapping address space), a service flow may be determined by
using a quintuple of an IP packet. Within a certain period of time
(one ID cycle), a fragment reassembly ID (not fragmented) of a data
packet of the service flow determined by a quintuple is unique.
Therefore, for a data packet of the service flow in a measurement
domain (which may include multiple different service flows), the
data packet of the service flow may be uniquely determined by using
a quintuple of the packet+a fragment reassembly ID at a transmit
end and a receive end. (For a same service flow, a fragment
reassembly ID of each data packet is different; for different
service flows, each service flow has a different quintuple.)
DCPs at the transmit end and receive end and managing TLPs, read
delay measurement information, service flow characteristic
information (a quintuple) and a fragment reassembly identifier (a
fragment reassembly ID), thereby matching timestamp information of
data packets of a same service flow.
For a fragmented data packet on the network, the DCPs managing the
TLPs read timestamp information of a first received data packet.
(Disorder and a delay of the fragmented data packet are often
shorter than a measurement period, and a cycling time of a fragment
reassembly ID at a host side is longer than the measurement
period.)
During the measurement implementing process illustrated in FIG. 4,
for the data packet of the service flow determined by using the
quintuple, the fragment reassembly ID is 100 at the transmit end,
and is also 100 at the receive end. According to this feature of
being unchanged, it may be determined that the timestamp
information acquired at the two ends is a measurement result of a
same data packet.
In addition, optionally, at the receive end, if the delay
measurement information carries a local period identifier (time
synchronization is not required), an order of the delay measurement
information and matching of two-way delay measurement may be
further determined.
With the method for measuring a network delay according to this
embodiment of the present application, transmit-end delay
measurement information obtained by an upstream TLP by measuring is
acquired by a DCP managing the upstream TLP, and transmitted to an
MCP. A DCP managing a downstream TLP acquires receive-end delay
measurement information obtained by the downstream TLP by measuring
and transmits the receive-end delay measurement information to the
MCP. Because the transmit-end delay measurement information further
includes transmit-end service flow characteristic information and a
transmit-end fragment reassembly identifier; and the receive-end
delay measurement information further includes receive-end service
flow characteristic information and a receive-end fragment
reassembly identifier, the MCP may be enabled to determine,
according to the transmit-end service flow characteristic
information, the transmit-end fragment reassembly identifier, the
receive-end service flow characteristic information, and the
receive-end fragment reassembly identifier, that transmit-end
timestamp information and receive-end timestamp information are
respectively acquired at a transmit end and a receive end of a
network from a same data packet that is in a service flow and to
which a delay measurement flag is added, there is a delay that the
data packet goes from the transit end to the receive end, thereby
performing fast and accurate measurement of the delay.
The foregoing embodiment describes a specific method performed by
the DCP according to the method for measuring a network delay in
the present application; the following describes in detail the
specific method performed by the TLP according to the method for
measuring a network delay in the present application.
FIG. 5 is a flowchart of Embodiment 6 of a method for measuring a
network delay according to the present application. As illustrated
in FIG. 5, the method according to this embodiment may include:
S200. Identify a service flow according to service flow
characteristic information, and determine whether the service flow
is a target service flow.
Specifically, TLPs are deployed at upstream transmit ends and
downstream receive ends first. Optionally, an upstream TLP and a
downstream TLP may be simultaneously deployed on user sides or
network sides of a transmit end and a receive end. Each service
flow has specific service flow characteristic information. The
service flow characteristic information has been described in
detail in Embodiment 5 of the method for measuring a network delay,
and is not described herein again. Therefore, when a service flow
enters the network, an upstream transmit port TLP first identifies
the service flow according to service flow characteristic
information. The identification process is performing matching
between preset service flow characteristic information and packet
header information of the service flow. If the preset service flow
characteristic information matches the packet header information of
the service flow, the upstream transmit port TLP determines that
the service flow is a target service flow. When a scenario of point
to multipoint transmission or multipoint to multipoint transmission
of the service flow occurs on the network, regardless of a specific
path of the service flow, whether data packets at the upstream
transmit ends and the downstream receive ends pertain to the same
service flow may be determined according to service flow
characteristic information of the service flow.
S202. If the service flow is the target service flow, add a delay
measurement flag to a data packet of the service flow, and acquire
data packet delay measurement information corresponding to the
delay measurement flag.
Specifically, the TLP adds a delay measurement flag to a data
packet of the service flow, and generates delay measurement
information, where the delay measurement information includes:
timestamp information, a service flow identifier, and a TLP
identifier. The timestamp information is a time point when the
delay measurement flag is added by the TLP. The service flow
identifier and the TLP identifier have been described in detail in
Embodiment 1 of the method for measuring a network delay, and are
not described herein again.
S204. Determine the delay measurement information.
Specifically, the TLP generates the delay measurement information,
so that after acquiring the delay measurement information, a DCP
transmits the delay measurement information to an MCP; therefore,
the MCP determines details about a delay according to the delay
measurement information.
With the method for measuring a network delay according to this
embodiment of the present application, a TLP identifies a service
flow according to service flow characteristic information, and
determines whether the service flow is a target service flow. If
the service flow is the target service flow, the TLP adds a delay
measurement flag to a data packet of the service flow, acquires
delay measurement information of the data packet, where the delay
measurement information of the data packet corresponds to the delay
measurement flag, and determines the delay measurement information,
so that after receiving the delay measurement information, the DCP
transmits the delay measurement information to an MCP; therefore,
the MCP determines details about a delay according to the delay
measurement information. This implements direct delay measurement
of the data packet of the service flow, and improves accuracy and
truthfulness of the delay measurement.
Based on Embodiment 6 of the method for measuring a network delay,
optionally, in the method according to Embodiment 7 of the method
for measuring a network delay according to the present application,
the adding a delay measurement flag to a data packet of the service
flow, and acquiring data packet delay measurement information
corresponding to the delay measurement flag includes:
adding, by an upstream TLP, a delay measurement flag to the data
packet of the target service flow, and acquiring transmit-end delay
measurement information of the data packet corresponding to the
delay measurement flag, where the transmit-end delay measurement
information includes: transmit-end timestamp information, a service
flow identifier, and a TLP identifier, so that after acquiring the
transmit-end delay measurement information, a DCP managing the
upstream TLP transmits the transmit-end delay measurement
information to an MCP; and
when identifying the data packet to which the delay measurement
flag is added, acquiring, by a downstream TLP, receive-end delay
measurement information of the data packet corresponding to the
delay measurement flag, where the receive-end delay measurement
information includes: receive-end timestamp information, a service
flow identifier, and a TLP identifier, so that after acquiring the
receive-end delay measurement information, a DCP managing the
downstream TLP transmits the receive-end delay measurement
information to the MCP.
Optionally, the delay measurement flag is added in a reserved bit
of TOS or a reserved bit of Flags in an IP header of the data
packet.
Specifically, a range that may be specified for the delay
measurement flag is a total of six bits in two fields TOS and Flags
of the IP header of the data packet, that is, bits 3 to 7 of TOS,
and bit 0 of Flags. Specifically, in different specific networks,
the last bits (bits 3 to 7) of TOS are generally not used,
especially bits 6 and 7, which are seldom used. Therefore, these
unused bits in the IP header may be used to add the Flag. In an IP
header of IPv4, bit 0 of Flags is the unique currently reserved bit
in the IP header. In a common IP header, this bit may be used to
add a flag to a data packet.
During specific implementation, the identifying a service flow
according to service flow characteristic information may
include:
identifying the service flow according to information about at
least two tuples in a quintuple.
Specifically, a quintuple refers to a source IP address or its IP
address prefix, a destination IP address or its IP address prefix,
a protocol type, a source protocol port number, and a destination
protocol port number that are in an IP header. In addition to a
quintuple, information may be added to the TOS field in the IP
header to specify the service flow characteristic information. The
fields may be all specified, so that the measurement of the service
flow is fine. Alternatively, the fields may be partially specified,
for example, at least information about two tuples: the source IP
address and the destination IP address; or the source IP address
prefix and the destination IP address prefix; or the source IP
address or its IP address prefix, the destination IP address or its
IP address prefix, and type of service (Type of Service,
hereinafter referred to as TOS) information.
In one aspect, based on Embodiment 7 of the method for measuring a
network delay according to the present application, a method for
measuring a network delay according to Embodiment 8 of the present
application further includes:
before adding the delay measurement flag to the data packet of the
target service flow, performing, by the upstream TLP, time
synchronization with the DCP managing the upstream TLP by using the
NTP or an IEEE 1588v2 clock; and before identifying the data packet
to which the delay measurement flag is added, performing, by the
downstream TLP, time synchronization with the DCP managing the
downstream TLP by using the NTP or an IEEE 1588v2 clock;
Specifically, time synchronization methods and principles have been
described in detail in Embodiment 3 of the method for measuring a
network delay according to the present application, and are not
described herein again. Referring to FIG. 2, by taking a
measurement period as a unit, the upstream TLP adds a delay
measurement flag to a data packet of the service flow within an
interval of each measurement period and generates transmit-end
delay measurement information and a measurement period identifier;
the downstream TLP identifies the data packet to which the delay
measurement flag is added by taking the measurement period as a
unit and generates receive-end delay measurement information and a
measurement period identifier. During delay measurement, it is
critical to determine that the transmit-end timestamp information
and the receive-end timestamp information are respectively acquired
by the upstream TLP and the downstream TLP after a same data packet
to which the delay measurement flag is added is transmitted over
the network. In this embodiment, before delay measurement is
performed at the upstream TLP and the downstream TLP, an external
time synchronization tool, that is, the NTP or an IEEE 1588v2
clock, may be separately deployed at the upstream TLP and the
downstream TLP, to implement time synchronization between the
upstream TLP and the DCP managing the upstream TLP, and time
synchronization between the downstream TLP and the DCP managing the
downstream TLP. Optionally, the DCP managing the upstream TLP and
the DCP managing the downstream TLP are also deployed with the
external time synchronization tool, that is, the NTP or an IEEE
1588v2 clock, to ensure time synchronization between the TLP and
the DCP, and between the DCPs. This ensures that within each
measurement period, the transmit-end measurement period identifier
generated by the upstream TLP matches the receive-end measurement
period identifier generated by the downstream TLP, and therefore
ensures that the transmit-end delay measurement information and the
receive-end delay measurement information that have the same
measurement period identifier match, so that the MCP accurately
determines details about a delay.
The adding a delay measurement flag to a data packet of the service
flow, and acquiring data packet delay measurement information
corresponding to the delay measurement flag further includes:
adding, by the upstream TLP, a delay measurement flag to the data
packet of the target service flow, acquiring a measurement period
identifier corresponding to the delay measurement flag, so that
after acquiring the measurement period identifier, the DCP managing
the upstream TLP transmits information about the measurement period
identifier to the MCP. The upstream TLP and the downstream TLP both
employ the NTP or an IEEE 1588v2 clock to perform time
synchronization with the DCP managing the upstream TLP and the DCP
managing the downstream TLP. Therefore, after the DCP managing the
upstream TLP and the DCP managing the downstream TLP read the
transmit-end delay measurement information and the receive-end
delay measurement information, the DCP managing the upstream TLP
acquires a corresponding measurement period identifier according to
the read transmit-end delay measurement information, and the DCP
managing the downstream TLP acquires a corresponding measurement
period identifier according to the read receive-end delay
measurement information. The two measurement period identifiers
pertain to a same measurement period and are consistent for the
data packet to which the delay measurement flag is added.
Specifically, if the upstream TLP identifies the target service
flow within 100 ms starting from start time of each measurement
period, the upstream TLP adds a delay measurement flag to the first
data packet of the service flow, records timestamp information t1
at that time, and acquires a measurement period identifier T[N], as
shown in FIG. 2. If the upstream TLP fails to identify the target
service flow, a delay measurement flag is not added to the data
packet within this measurement period.
acquiring, by the downstream TLP, the start time of each
measurement period within the measurement period, and when
identifying, within each measurement period, the data packet to
which the delay measurement flag is added, acquiring the
measurement period identifier corresponding to the delay
measurement flag, so that after acquiring the start time and the
measurement period identifier, the DCP managing the downstream TLP
transmits information about the measurement period identifier to
the MCP.
Specifically, referring to FIG. 2, assuming that a measurement
period is T, the downstream TLP records, starting from start time
of the N.sup.th measurement period, start time t0 of the
measurement period. If a data packet with a delay measurement flag
is identified within the measurement period, the downstream TLP
records timestamp information t3 at that time, and generates a
measurement period identifier M and receive-end delay measurement
information. When the N.sup.th measurement period ends, the DCP
managing the downstream TLP acquires the receive-end delay
measurement information, the measurement period identifier T[N],
and the start time t0, where the receive-end delay measurement
information includes: the timestamp information t3, a service flow
identifier, and a TLP identifier. The DCP managing the downstream
TLP performs calculation on the timestamp information t3 and the
start time t0. If t3-t0<2T/3, the timestamp information t3
pertains to the N.sup.th measurement period; if t3-t0.gtoreq.2T/3,
the timestamp information t3 pertains to the N+1.sup.th measurement
period. In this case, the DCP managing the downstream TLP increases
the period identifier T[N] by 1 to obtain T[N+1]. In this way, in
cases of out-of-order data packets due to a time synchronization
error, after receiving the receive-end delay measurement
information and the measurement period identifier that are
transmitted by the DCP managing the downstream TLP, the MPC is
still capable of determining, according to the measurement period,
that the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same data packet, thereby accurately and directly implementing
delay measurement.
In addition, in the method for measuring a network delay according
to this embodiment, within each measurement period, a TLP
identifies a data packet of a service flow, and adds a delay
measurement flag to the data packet within the measurement period.
Optionally, the TLP adds a delay measurement flag to only one data
packet.
With the method for measuring a network delay according to this
embodiment of the present application, before adding a delay
measurement flag to a data packet of a target service flow, an
upstream TLP performs time synchronization with a DCP managing the
upstream TLP by using the NTP or an IEEE 1588v2 clock. Before
identifying the data packet to which the delay measurement flag is
added, a downstream TLP performs time synchronization with a DCP
managing the downstream TLP by using the NTP or an IEEE 1588v2
clock, ensuring time synchronization between the upstream TLP and
the downstream TLP, thereby ensuring that within a same period, a
measurement period identifier generated by the upstream TLP is
consistent with a measurement period identifier generated by the
downstream TLP. In this way, an MCP determines, according to the
same measurement period identifier, that transmit-end timestamp
information and receive-end timestamp information are timestamp
information corresponding to a same data packet. In addition, in
cases of out-of-order data packets due to a time synchronization
error, the downstream TLP acquires start time of each measurement
period within the measurement period, and acquires a measurement
period identifier corresponding to the delay measurement flag when
identifying the data packet to which the delay measurement flag is
added within each measurement period, so that after the DCP
managing the downstream TLP acquires the start time and the
measurement period identifier, the DCP determines, according to the
start time and the receive-end timestamp information, a correct
measurement period identifier, and transmits the correct
measurement period identifier to the MCP; therefore, the MCP
accurately determines details about a delay.
In another aspect, based on Embodiment 7 of the method for
measuring a network delay according to the present application, a
method for measuring a network delay according to Embodiment 9 of
the present application further includes:
transmitting, by the upstream TLP, a measurement packet to the
downstream TLP, where the measurement packet includes: transmit-end
timestamp information;
receiving, by a receiving module of the downstream TLP, the
measurement packet, generating arrival timestamp information of the
measurement packet, and transmitting the measurement packet and the
arrival timestamp information to the DCP managing the downstream
TLP, so that the DCP determines whether the arrival timestamp
information and the receive-end timestamp information pertain to a
preset duration range, and if the arrival timestamp information and
the receive-end timestamp information pertain to the preset
duration range, determines that the transmit-end timestamp
information and the receive-end timestamp information pertain to
the same measurement period, and transmits a result of the
determining to an MCP.
Specifically, referring to FIG. 3, the upstream TLP performs delay
measurement on the service flow by taking the measurement period T
as a unit. However, time synchronization is not performed for the
measurement periods of the upstream TLP and the downstream TLP by
using a time synchronization tool. To ensure that transmit-end
delay measurement information and receive-end delay measurement
information pertain to a same measurement period, in this
embodiment, when the upstream TLP generates transmit-end delay
measurement information by taking a measurement period as a unit,
where the transmit-end delay measurement information includes
timestamp information, a service flow identifier, and a TLP
identifier, and when the DCP managing the upstream TLP acquires the
transmit-end delay measurement information, the upstream TLP
generates a measurement packet including transmit-end timestamp
information t1, and transmits the measurement packet to the
downstream TLP at the receive end; the downstream TLP generates
receive-end delay measurement information within a measurement
period and receives the measurement packet; the DCP managing the
downstream TLP acquires the receive-end delay measurement
information and the measurement packet, and compares the
measurement packet with the receive-end delay measurement
information. Specific comparison methods and technical solutions
have been described in Embodiment 4 of the method for measuring a
network delay, and are not described herein again.
In addition, in the method for measuring a network delay according
to this embodiment, a TLP identifies a data packet of a service
flow, and adds a delay measurement flag to the data packet within a
measurement period. Optionally, within each measurement period, the
TLP adds a delay measurement flag to only one data packet.
With the method for measuring a network delay according to this
embodiment of the present application, an upstream TLP transmits a
measurement packet to a downstream TLP, where the measurement
packet includes transmit-end timestamp information; the downstream
TLP transmits the received measurement packet to a DCP, so that the
DCP determines whether transmit-end timestamp information and
receive-end timestamp information pertain to a preset duration
range; if the transmit-end timestamp information and the
receive-end timestamp information pertain to the preset duration
range, the DCP determines that the transmit-end timestamp
information and the receive-end timestamp information pertain to a
same measurement period, and transmits a result of the determining
to an MCP, thereby ensuring that transmit-end delay measurement
information and receive-end delay measurement information pertain
to a same measurement period, and implementing direct and accurate
delay measurement of a service flow.
In still another aspect, based on Embodiment 7 of the method for
measuring a network delay according to the present application, a
method for measuring a network delay according to Embodiment 10 of
the present application further includes:
The transmit-end delay measurement information further includes:
transmit-end service flow characteristic information and a
transmit-end fragment reassembly identifier; and the receive-end
delay measurement information further includes: receive-end service
flow characteristic information and a receive-end fragment
reassembly identifier;
so that the DCP managing the upstream TLP acquires the transmit-end
delay measurement information and transmits the transmit-end delay
measurement information to the MCP, and the DCP managing the
downstream TLP acquires the receive-end delay measurement
information and transmits the receive-end delay measurement
information to the MCP; therefore, the MCP determines, according to
the transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, whether the transmit-end timestamp
information and the receive-end timestamp information are timestamp
information corresponding to a same service flow.
Specifically, referring to FIG. 4, during network delay
measurement, it is critical to determine that transmit-end
timestamp information and receive-end timestamp information are
respectively acquired by the upstream TLP and the downstream TLP
after a same data packet to which a delay measurement flag is added
is transmitted over the network. In this embodiment, accordingly,
when a service flow is identified by the upstream TLP, the upstream
TLP adds a delay measurement flag 1 to a data packet A of the
target service flow. The transmit-end delay measurement information
generated by the upstream TLP includes transmit-end timestamp
information, a service flow identifier, a TLP identifier,
transmit-end service flow characteristic information, and a
transmit-end fragment reassembly identifier. The DCP managing the
upstream TLP acquires the transmit-end delay measurement
information, and transmits the transmit-end delay measurement
information to the MCP. In addition, because a timestamp is not
added to a data packet based on a period in this embodiment, the
TLP according to this embodiment may add delay measurement flags
densely to a data packet of a service flow. When the downstream TLP
identifies the data packet A with the delay measurement flag, the
downstream TLP generates receive-end delay measurement information,
which includes receive-end timestamp information, a service flow
identifier, a TLP identifier, receive-end service flow
characteristic information, and a receive-end fragment reassembly
identifier, and the DCP managing the downstream TLP acquires the
receive-end delay measurement information, and transmits the
receive-end delay measurement information to the MCP. The MCP may
determine, according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier,
that the transmit-end timestamp information and the receive-end
timestamp information are respectively acquired by the transmit end
and the receive end of the network after a same data packet of the
service flow to which a delay measurement flag is added is
transmitted, there is a delay that the data packet goes from the
transit end to the receive end. In this way, the MCP performs delay
measurement according to the matched transmit-end delay measurement
information and receive-end delay measurement information. The
service flow characteristic information and the fragment reassembly
identifier have been described in Embodiment 5 of the method for
measuring a network delay, and are not described herein again.
With the method for measuring a network delay according to this
embodiment of the present application, after identifying and
performing delay measurement on a data packet of a target service
flow, an upstream TLP records transmit-end service flow
characteristic information and a transmit-end fragment reassembly
identifier, and the upstream TLP generates transmit-end delay
measurement information; the transmit-end delay measurement
information according to this embodiment of the present application
not only includes transmit-end timestamp information, a service
flow identifier, and a TLP identifier, but also includes the
transmit-end service flow characteristic information and the
transmit-end fragment reassembly identifier, so that a DCP managing
the upstream TLP acquires the transmit-end delay measurement
information and transmits the transmit-end delay measurement
information to an MCP; and a downstream TLP performs similar
operations, so that a DCP managing the downstream TLP acquires the
receive-end delay measurement information and transmits the
receive-end delay measurement information to the MCP; therefore,
the MCP implements matching between the transmit-end delay
measurement information and the receive-end delay measurement
information according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier. In
this way, accuracy of direct delay measurement is ensured.
The following describes in detail the method performed by the MCP
in the method for measuring a network delay according to the
present application.
FIG. 6 is a flowchart of Embodiment 11 of a method for measuring a
network delay according to the present application. As illustrated
in FIG. 6, the method according to this embodiment may include the
following steps:
S300. Receive transmit-end delay measurement information
transmitted by a DCP corresponding to an upstream TLP and
receive-end delay measurement information transmitted by a DCP
corresponding to a downstream TLP.
Specifically, the transmit-end delay measurement information
includes: transmit-end timestamp information, a service flow
identifier, and a TLP identifier, and the receive-end delay
measurement information includes: receive-end timestamp
information, a service flow identifier, and a TLP identifier.
S302. Determine details about a single network delay according to
the transmit-end delay measurement information and the receive-end
delay measurement information.
Specifically, an MCP performs, according to the transmit-end delay
measurement information and the receive-end delay measurement
information, delay calculation on the transmit-end timestamp
information and the receive-end timestamp information pertaining to
a same data packet of a same service flow. In addition, in the
method for measuring a network delay according to this embodiment
of the present application, the MCP may be deployed on any network
element node on an entire network. Optionally, the MCP may be
deployed on a network element node with powerful functions.
Further, the MCP, the DCPs, and the TLPs are connected based on a
management network.
With the method for measuring a network delay according to this
embodiment of the present application, an MCP receives transmit-end
delay measurement information transmitted by a DCP corresponding to
an upstream TLP, and receive-end delay measurement information
transmitted by a DCP corresponding to a downstream TLP, and the MCP
determines details about a single network delay according to the
transmit-end delay measurement information and the receive-end
delay measurement information, thereby implementing direct and
accurate delay measurement of a service flow.
In one aspect, based on Embodiment 11 of the method for measuring a
network delay according to the present application, a method for
measuring a network delay according to Embodiment 12 of the present
application further includes:
receiving, by an MCP, a measurement period identifier transmitted
by the DCP managing the upstream TLP, receiving, by the MCP, a
measurement period identifier transmitted by the DCP managing the
downstream TLP, determining, by the MCP according to the
measurement period identifier transmitted by the DCP managing the
upstream TLP and the measurement period identifier transmitted by
the DCP managing the downstream TLP, whether the transmit-end delay
measurement information and the receive-end delay measurement
information pertain to a same measurement period, and if the
transmit-end delay measurement information and the receive-end
delay measurement information pertain to a same measurement period,
determining, by the MCP, details about a single network delay
according to the transmit-end delay measurement information and the
receive-end delay measurement information.
Specifically, when delay measurement is performed on a target
service flow, optionally the MCP maintains a measurement data
summary table for the target service flow. Table 1 is a measurement
data summary table for the target service flow according to this
embodiment. With reference to Table 1, the following describes how
to determine details about a network delay according to this
embodiment.
TABLE-US-00001 TABLE 1 Measurement data summary table for the
target service flow Service TLPs (n TLPs) Data flow on the left
side TLPs (m TLPs) on the right side Data packet identifier Data
type TLP (1) . . . TLP (n) TLP (1) . . . TLP (m) arrival flag N
Forward Timestamp Transmit-end Invalid Invalid Invalid . . .
Receive-end All arrive service timestamp timestamp flow information
information identifier Backward Timestamp Receive-end Invalid
Invalid Transmit-end Invalid Inval- id All arrive service timestamp
timestamp flow information information identifier N - 1 Forward
Timestamp Transmit-end Invalid Invalid Not arrive Not Not arrive
Arrive in service timestamp arrive the flow information upstream
identifier Backward Timestamp Receive-end Invalid Invalid Invalid
Invalid Invalid Ar- rive in service timestamp the flow information
downstream identifier . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . .
With respect to Table 1, the measurement data summary table for the
target service flow, it should be noted that, in Table 1, concepts
of "TLPs on the left side" and "TLPs on the right side" are defined
by using the network as a boundary. One network side is defined as
the left side, and TLPs deployed on ports on the left side are the
TLPs on the left side; and the TLPs on the right side are defined
accordingly. During the process of measuring a network delay
according to this embodiment of the present application, it is
possible that two target service flows that are in opposite
directions exist simultaneously. In this case, the MCP may define
one of the target service flows as a forward service flow and
define the other target service flow as a backward service flow
according to source IP addresses or their IP address prefixes and
destination IP addresses or their IP address prefixes in quintuples
of the two target service flows. For example, a range of a network
covers all devices and subnetworks including a left-side port
device to a right-side port device. Assuming that a target service
flow A enters the network from TLPs on the left-side port device
and leaves the network from TLPs on the right-side port device, and
a target service flow B enters the network from the TLPs on the
right-side port device and leaves the network from the TLPs on the
left-side port device. With respect to the target service flow A,
the left-side port device is a transmit-end device, and the
left-side TLPs are upstream transmit ends; with respect to the
target service flow B, the left-side port device is a receive-end
device, and the left-side TLPs are downstream receive ends.
Therefore, during delay measurement for two target service flows
that are in opposite directions based on a same TLP, in Table 1,
the measurement data summary table for the target service flow,
which is maintained by the MCP, within each period, the MCP
maintains a data entry for the forward service flow and a data
entry for the backward service flow, thereby implementing a
function of simultaneously performing delay measurement on two
service flows that are in opposite directions.
The DCP reads delay measurement information of the TLPs and
transmits the delay measurement information to the MCP. First, the
MCP may find, according to the service flow identifier, or
optionally by using a target service flow ID as the service flow
identifier, a corresponding measurement data summary table for the
target service flow; and then the MCP fills data into the
corresponding measurement data summary table for the target service
flow according to the service flow identifier, the measurement
period identifier and the TLP identifier. In this embodiment, in
Table 1, the measurement period identifier may uniquely determine
that transmit-end delay measurement information and receive-end
delay measurement information pertain to a same data packet, that
is, with respect to entries of the data packet in Table 1, one
measurement period identifier corresponds to one data packet.
With respect to the process of receiving the delay measurement
information and maintaining Table 1 by the MCP, it should be noted
that, because delay measurement is directed to data packets, during
a transmission process of a data packet, there is only one piece of
transmit-end timestamp information generated by an upstream TLP and
one piece of receive-end timestamp information generated by a
downstream TLP. Therefore, referring to Table 1, when the MCP
receives a piece of delay measurement information and updates the
delay measurement information to data entries of one TLP of the
left-side TLPs, other TLP data entries of the left-side TLPs of the
data packet are set as invalid by the MCP; and with respect to the
right-side TLPs, the MCP performs similar operations.
Referring to Table 1, assuming that one service flow is a forward
service flow, each data entry of a data packet of the forward
service flow corresponds to a data arrival flag in the measurement
data summary table for the target service flow. When delay
measurement information of the left-side TLPs and the right-side
TLPs of a data packet corresponding to each measurement period
identifier does not arrive, the MCP sets the data arrival flag
within the measurement period as "Not arrive". For example, in
Table 1, in data entries corresponding to the forward service flow
with the measurement period identifier N-1, among the left-side
TLPs, the MCP receives transmit-end delay measurement information
obtained by the first TLP by measurement and transmitted by the DCP
managing the upstream TLP, but delay measurement information in the
right-side TLPs does not arrive. In this case, the MCP sets an
arrival flag of a corresponding data entry as "Arrive in the
upstream". After the MCP receives receive-end delay measurement
information transmitted by the DCP managing the downstream TLP, the
MCP updates Table 1, and fills receive-end timestamp information
carried in the receive-end delay measurement information to a
corresponding TLP data entry, and sets an arrival flag of a
corresponding data entry as "All arrive".
After the MCP detects that in a measurement period identifier, a
data arrival flag of a data entry corresponding to a forward
service flow identifier or a backward service flow identifier is
set to "All arrive", the MCP performs the delay calculation
according to the corresponding transmit-end timestamp information
and the corresponding receive-end timestamp information. A specific
formula is as follows: Delay=Receive-end timestamp
information-Transmit-end timestamp information
That is, a difference between a time point when an upstream TLP
adds a delay measurement flag to a data packet and a time point
when the data packet is identified by a downstream TLP.
Referring to Table 1, with respect to one measurement period
identifier, two-way delay measurement may be performed on a forward
service flow and a backward service flow simultaneously. In this
case, the MCP performs experimental calculation according to
transmit-end timestamp information and receive-end timestamp
information corresponding to the forward service flow, and
transmit-end timestamp information and receive-end timestamp
information corresponding to the backward service flow. A specific
formula is as follows: Delay=(Receive-end timestamp information
corresponding to a backward service flow-Transmit-end timestamp
information corresponding to a forward service flow)-(Transmit-end
timestamp information corresponding to the backward service
flow-Receive-end timestamp information corresponding to the forward
service flow)
FIG. 7 is a schematic diagram of two-way delay measurement in
Embodiment 12 of a method for measuring a network delay according
to the present application. Referring to FIG. 7, the foregoing
principles and methods for calculating a two-way delay are further
described.
As illustrated in FIG. 7, assuming that the service flow at the
upper part in FIG. 7 is a forward service flow, the TLP on the left
side of the network adds a delay measurement flag 1 to a data
packet, and records time t1. Therefore, transmit-end timestamp
information corresponding to the forward service flow is t1. When
identifying the data packet with the delay measurement flag 1, the
TLP on the right side records time t2, that is, receive-end
timestamp information corresponding to the forward service flow is
t2. The TLP on the left side and the TLP on the right side
respectively generate transmit-end delay measurement information
and receive-end delay measurement information, and a DCP managing
the TLP on the left side (the TLP on the left side is an upstream
TLP for the forward service flow) and a DCP managing the TLP on the
right side respectively read the transmit-end delay measurement
information and the receive-end delay measurement information, and
transmit the transmit-end delay measurement information and the
receive-end delay measurement information to the MCP. Likewise,
with respect to a backward service flow, the MCP receives
transmit-end timestamp information t3 and receive-end timestamp
information t4. The MCP calculates a delay of a data packet of the
forward service flow as t2-t1, and calculates a delay of a data
packet of the backward service flow as t4-t3. In this case, a
two-way delay is (t2-t1)+(t4-t3), that is, (t4-t1)-(t3-t2).
With the method for measuring a network delay according to this
embodiment, first, an MCP performs time synchronization with DCPs
by using an external time synchronization tool; then the MCP
receives delay measurement information transmitted by the DCPs
corresponding to an upstream TLP and a downstream TLP, where the
delay measurement information includes transmit-end delay
measurement information and receive-end delay measurement
information; the MCP records and maintains a measurement data
summary table for a target service flow, the transmit-end delay
measurement information of the upstream TLP at the transmit end and
the receive-end delay measurement information of the downstream TLP
at the receive end; and the MCP performs, according to the
measurement data summary table for the target service flow by
taking each measurement period as a unit, delay calculation for the
transmit-end delay measurement information and the receive-end
measurement information, thereby directly and accurately
determining details about a delay of a service flow on the
network.
In another aspect, based on Embodiment 11 of the method for
measuring a network delay according to the present application, a
method for measuring a network delay according to Embodiment 13 of
the present application further includes:
receiving, by an MCP, the transmit-end delay measurement
information transmitted by the DCP corresponding to the upstream
TLP, receiving, by the MCP, the receive-end delay measurement
information that is determined as pertaining to a same measurement
period as the transmit-end delay measurement information and is
transmitted by the DCP corresponding to the downstream TLP, and
determining, by the MCP, details about a single network delay
according to the transmit-end delay measurement information and the
receive-end delay measurement information.
Specifically, with respect to a network on which no external time
synchronization tool is employed, to ensure that transmit-end delay
measurement information and receive-end delay measurement
information pertain to a same measurement period, it needs to
ensure that the transmit-end delay measurement information and the
receive-end delay measurement information pertain to a same data
packet. With the methods according to Embodiments 4 and 9 of the
method for measuring a network delay according to the present
application, an upstream TLP, a downstream TLP, and a DCP managing
the downstream TLP performs matching between transmit-end delay
measurement information and receive-end delay measurement
information, and the DCP transmits the transmit-end delay
measurement information and the receive-end delay measurement
information that are consistent to an MCP. The MCP according to
this embodiment also maintains Table 1. According to the
transmit-end delay measurement information and the receive-end
delay measurement information that are consistent, by referring to
FIG. 1, the MCP updates the transmit-end delay measurement
information and the receive-end delay measurement information to
data entries of a corresponding data packet in Table 1. It should
be noted that, in Table 1 maintained by the MCP in this embodiment,
the DCP may transmit the transmit-end delay measurement information
and the receive-end delay measurement information that are
consistent to the MCP, the MCP may update the transmit-end delay
measurement information and the receive-end delay measurement
information to data entries of the corresponding data packet, and
the MCP determines details about a delay. The DCP may also
determine details about a delay according to the transmit-end delay
measurement information and receive-end delay measurement
information that are consistent, and then transmits the determined
details about a delay to the MCP. In this case, the MCP directly
receives the details about a delay.
Data entries corresponding to a data packet are determined
according to transmit-end delay measurement information and
receive-end delay measurement information that are consistent, and
then the MCP performs delay calculation. The specific calculation
methods and formulas have been described in detail in Embodiment 12
of the method for measuring a network delay according to the
present application, and are not described herein again.
With the method for measuring a network delay according to this
embodiment, an MCP receives transmit-end delay measurement
information transmitted by a DCP corresponding to an upstream TLP,
the MCP receives receive-end delay measurement information that is
determined as pertaining to a same measurement period as the
transmit-end delay measurement information and is transmitted by a
DCP corresponding to a downstream TLP, and the MCP measures details
about a single network delay according to the transmit-end delay
measurement information and the receive-end delay measurement
information, thereby ensuring that the MPC accurately and directly
measures details about a network flow delay without a time
synchronization tool.
In still another aspect, based on Embodiment 11 of the method for
measuring a network delay according to the present application, a
method for measuring a network delay according to Embodiment 14 of
the present application further includes:
receiving, by an MCP, the transmit-end delay measurement
information transmitted by the DCP corresponding to the upstream
TLP, where the transmit-end delay measurement information includes:
the timestamp information, the service flow identifier, the TLP
identifier, transmit-end service flow characteristic information,
and a transmit-end fragment reassembly identifier;
receiving, by the MCP, the receive-end delay measurement
information transmitted by the DCP corresponding to the downstream
TLP, where the receive-end delay measurement information includes:
the timestamp information, the service flow identifier, the TLP
identifier, receive-end service flow characteristic information,
and a receive-end fragment reassembly identifier; and
determining, by the MCP according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier,
whether the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same service flow; and if the transmit-end timestamp information
and the receive-end timestamp information are timestamp information
corresponding to a same service flow, determining, by the MCP,
details about a single network delay according to the transmit-end
delay measurement information and the receive-end delay measurement
information.
Specifically, in cooperation with the methods according to
Embodiments 5 and 10 of the method for measuring a network delay
according to the present application, the MCP in this embodiment of
the present application may determine, according to the
transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, whether the transmit-end timestamp
information and the receive-end timestamp information is timestamp
information pertaining to a same data packet. If the transmit-end
timestamp information and the receive-end timestamp information is
timestamp information pertaining to a same data packet, the MCP
updates the transmit-end timestamp information and the receive-end
timestamp information to data entries of a corresponding data
packet in Table 1; if the transmit-end timestamp information and
the receive-end timestamp information are not timestamp information
pertaining to a same data packet, the MCP updates the transmit-end
timestamp information and the receive-end timestamp information to
data entries of respective data packets. Referring to Table 1, the
operation process of the MCP is described in detail. After the MCP
receives the transmit-end delay measurement information, because
with respect to a service flow, service flow characteristic
information is unique, the MCP determines, according to the
transmit-end service flow characteristic information, that is, a
quintuple: a source IP address, a destination IP address, a
protocol type, a source protocol port number, and a destination
protocol port number, which service flow the transmit-end delay
measurement information pertains to. After determining that the
transmit-end delay measurement information pertains to a target
service flow, the MCP finds a measurement data summary table for
the target service flow corresponding to the service flow. In
addition, because a transmit-end fragment reassembly identifier is
also unique for a data packet, the MCP determines, according to the
transmit-end fragment reassembly identifier, that the transmit-end
delay measurement information pertains to a specific data packet of
the target service flow, for example, the N.sup.th data packet, and
therefore the MCP updates the transmit-end timestamp information
carried in the transmit-end delay measurement information to data
entries of a corresponding N.sup.th data packet. With respect to
receive-end delay measurement information, the MCP also performs
similar operations to identify the receive-end delay measurement
information, and updates the identified receive-end delay
measurement information to entries of the corresponding data
packet; and subsequently the MCP performs corresponding delay
calculations. The specific calculation methods and formulas have
been described in detail in Embodiment 12 of the method for
measuring a network delay according to the present application, and
are not described herein again.
With the method for measuring a network delay according to this
embodiment, an MCP receives transmit-end delay measurement
information transmitted by a DCP corresponding to an upstream TLP,
where the transmit-end delay measurement information includes
timestamp information, a service flow identifier, a TLP identifier,
transmit-end service flow characteristic information, and a
transmit-end fragment reassembly identifier; the MCP receives
receive-end delay measurement information transmitted by a DCP
corresponding to a downstream TLP, where the receive-end delay
measurement information includes timestamp information, a service
flow identifier, a TLP identifier, receive-end service flow
characteristic information, and a receive-end fragment reassembly
identifier; and the MCP performs identification and matching
according to the transmit-end service flow characteristic
information, the transmit-end fragment reassembly identifier, the
receive-end service flow characteristic information, and the
receive-end fragment reassembly identifier, thereby ensuring that
the transmit-end delay measurement information and the receive-end
delay measurement information pertain to a same data packet; and
the MCP performs delay calculation for the matched transmit-end
delay measurement information and receive-end delay measurement
information, thereby implementing direct and accurate measurement
of a delay of a service flow.
FIG. 8 is a schematic structural diagram of Embodiment 1 of a DCP
according to the present application. As illustrated in FIG. 8, the
DCP includes: an acquiring module 10 and a transmitting module
12.
The acquiring module 10 is configured to acquire delay measurement
information obtained by measuring a service flow by at least one
TLP, where the delay measurement information includes: timestamp
information, a service flow identifier, and a TLP identifier.
The transmitting module 12 is configured to transmit the delay
measurement information to a measurement control point MCP, so that
the MCP determines details about a network delay according to the
timestamp information, the service flow identifier, and the TLP
identifier.
Specifically, DCPs are deployed on a transmit-end device and a
receive-end device. Working principles and technical solutions of
DCPs have been described in detail in Embodiment 1 of the method
for measuring a network delay according to the present application,
and are not described herein again.
The DCP according to this embodiment may be used to perform the
technical solution in the embodiment illustrated in FIG. 1. The
implementation principles and technical effects are similar, and
are not described herein again.
With respect to the DCP according to this embodiment, when the DCP
is a DCP managing an upstream TLP, the acquiring module 10 is
specifically configured to acquire transmit-end delay measurement
information obtained by measuring a transmitted service flow by at
least one upstream TLP, and the transmitting module 12 is
specifically configured to transmit the transmit-end delay
measurement information to the MCP, where the transmit-end delay
measurement information includes: transmit-end timestamp
information, a service flow identifier, and a TLP identifier. The
specific principles and methods have been described in detail in
Embodiment 2 of the method for measuring a network delay according
to the present application, and are not described herein again.
Alternatively, when the DCP is a DCP managing a downstream TLP, the
acquiring module 10 is specifically configured to acquire
receive-end delay measurement information obtained by measuring a
received service flow by at least one downstream TLP, and the
transmitting module 12 is specifically configured to transmit the
receive-end delay measurement information to the MCP, where the
transmit-end delay measurement information includes: receive-end
timestamp information, a service flow identifier, and a TLP
identifier. The specific principles and methods have been described
in detail in Embodiment 2 of the method for measuring a network
delay according to the present application, and are not described
herein again.
In one aspect, based on FIG. 8, FIG. 9 is a schematic structural
diagram of Embodiment 2 of a DCP according to the present
application. As illustrated in FIG. 9, an acquiring module 20 in
the DCP according to Embodiment 2 of the present application
includes: a first acquiring unit 200 and a period identifier
acquiring unit 202.
The first acquiring unit 200 is configured to acquire the
transmit-end delay measurement information obtained by measuring
the transmitted service flow by the at least one upstream TLP, or
acquire the receive-end delay measurement information obtained by
measuring the received service flow by the at least one downstream
TLP.
The period identifier acquiring unit 202 is configured to: when a
measurement period ends, the period identifier acquiring unit 202
acquires a measurement period identifier, and transmits the
measurement period identifier to the MCP; or when a measurement
period of the DCP managing the downstream TLP starts, the period
identifier acquiring unit 202 may acquire a boundary time point of
each measurement period by using the NTP or an IEEE 1588v2 clock,
that is, acquire start time of the measurement period; where if a
difference between the start time and the timestamp information is
less than or equal to a preset duration, the receive-end delay
measurement information pertains to measurement information
corresponding to the measurement period identifier; and if the
difference between the start time and the timestamp information is
greater than the preset duration, the measurement period identifier
is increased by 1, the timestamp information pertains to a next
measurement period, and a measurement period identifier of the DCP
managing the downstream TLP within the measurement period is
acquired. Optionally, the preset duration is 2/3 of a duration of
the measurement period. The specific working principles and methods
have been described in detail in Embodiment 3 of the method for
measuring a network delay according to the present application and
FIG. 2, and are not described herein again.
Optionally, a corresponding DCP may directly read the transmit-end
delay measurement information and the receive-end delay measurement
information generated by the upstream TLP and the downstream TLP
respectively, and the period identifier acquiring unit 202 of the
DCP acquires two measurement period identifiers according to the
transmit-end delay measurement information and the receive-end
delay measurement information respectively. In addition, for a data
packet to which a delay measurement flag is added within a
measurement period, the two measurement period identifiers acquired
by the DCP managing the upstream TLP and the DCP managing the
downstream TLP are consistent.
As illustrated in FIG. 9, a transmitting module 22 in the DCP
according to Embodiment 2 of the present application includes a
first transmitting unit 220 and a second transmitting unit 222.
The first transmitting unit 220 is configured to transmit the
transmit-end delay measurement information to the MCP, or transmit
the receive-end delay measurement information to the MCP.
The second transmitting unit 222 is configured to: when the
measurement period ends, transmit the measurement period identifier
acquired by a period identifier acquiring unit 202 of the DCP
managing the upstream TLP to the MCP, or transmit the measurement
period identifier acquired by a period identifier acquiring unit
202 of the DCP managing the downstream TLP to the MCP.
Optionally, the DCP according to Embodiment 2 of the present
application further includes: a time synchronization module 24.
The time synchronization module 24 is configured to: before the
acquiring module 20 acquires delay measurement information obtained
by at least one TLP by measuring a service flow, perform time
synchronization with the TLP by using the NTP or an IEEE 1588v2
clock, and perform time synchronization between the DCP managing
the upstream TLP and the DCP managing the downstream TLP by using
the NTP or an IEEE 1588v2 clock. The NTP or an IEEE 1588v2 clock,
and time synchronization methods and principles have been described
in detail in Embodiment 3 of the method for measuring a network
delay according to the present application, and are not described
herein again.
The DCP according to this embodiment may be used to perform the
technical solution in Embodiment 3 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In another aspect, based on FIG. 8, FIG. 10 is a schematic
structural diagram of a DCP according to Embodiment 3 of the
present application. As illustrated in FIG. 8, the DCP includes: an
acquiring module 30, a determining module 32, and a transmitting
module 34. The acquiring module 30 includes a second acquiring unit
300 and a measurement packet acquiring unit 302.
The second acquiring unit 300 is configured to acquire the
transmit-end delay measurement information obtained by measuring
the transmitted service flow by the at least one upstream TLP, or
acquire the receive-end delay measurement information obtained by
measuring the received service flow by the at least one downstream
TLP.
Specifically, the transmit-end delay measurement information
includes: transmit-end timestamp information, a service flow
identifier, and a TLP identifier; and the receive-end delay
measurement information includes: receive-end timestamp
information, a service flow identifier, and a TLP identifier.
The measurement packet acquiring unit 302 is configured to acquire
a measurement packet transmitted by the upstream TLP and received
by the at least one downstream TLP, and arrival timestamp
information of the measurement packet, which is generated when the
measurement packet arrives at the downstream TLP, where the
measurement packet includes: transmit-end timestamp
information;
The determining module 32 is specifically configured to determine
whether the arrival timestamp information and the receive-end
timestamp information pertain to a preset duration range; and if
the arrival timestamp information and the receive-end timestamp
information pertain to the preset duration range, determine that
the transmit-end timestamp information and the receive-end
timestamp information pertain to a same data packet. The specific
determining principles and methods have been described in detail in
Embodiment 4 of the method for measuring a network delay according
to the present application, and are not described herein again.
The transmitting module 34 is specifically configured to transmit a
result of the determining to the MCP.
It should be noted that, the determining module 32 may transmit the
transmit-end timestamp information and the receive-end timestamp
information that pertain to a same data packet to the transmitting
module 34, and the transmitting module 34 transmits the
transmit-end timestamp information and the receive-end timestamp
information to the MCP, and the MCP performs delay calculation.
Alternatively, the determining module 32 may directly determine
details about a delay of the data packet within the period
according to the transmit-end timestamp information and the
receive-end timestamp information that pertain to a same
measurement period, and then transmits calculated details about the
delay to the MCP.
The DCP according to this embodiment may be used to perform the
technical solution in Embodiment 4 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In still another aspect, referring to FIG. 8, a DCP according to
Embodiment 4 of the present application includes: an acquiring
module 10 and a transmitting module 12.
With respect to the acquiring module 10, when the DCP is a data
collecting point managing an upstream TLP, the acquiring module 10
is specifically configured to acquire transmit-end delay
measurement information, where the transmit-end delay measurement
information further includes: transmit-end service flow
characteristic information and a transmit-end fragment reassembly
identifier. When the DCP is a data collecting point managing a
downstream TLP, the acquiring module 10 is specifically configured
to acquire receive-end delay measurement information, where the
receive-end delay measurement information further includes:
receive-end service flow characteristic information and a
receive-end fragment reassembly identifier.
With respect to the transmitting module 12, when the DCP is a data
collecting point managing an upstream TLP, the transmitting module
12 is specifically configured to transmit the transmit-end delay
measurement information to the MCP, so that the MCP determines,
according to the transmit-end service flow characteristic
information, the transmit-end fragment reassembly identifier, the
receive-end service flow characteristic information, and the
receive-end fragment reassembly identifier, that the transmit-end
timestamp information and the receive-end timestamp information are
timestamp information corresponding to a same service flow.
Specifically, service flow characteristic information and a
fragment reassembly identifier, and corresponding operations
performed by the DCP based on the service flow characteristic
information and the fragment reassembly identifier have been
described in detail in Embodiment 5 of the method for measuring a
network delay, and are not described herein again.
The DCP according to this embodiment may be used to perform the
technical solution in Embodiment 5 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
FIG. 11 is a schematic structural diagram of Embodiment 1 of a TLP
according to the present application. As illustrated in FIG. 11,
the TLP includes: an identifying module 40, a timestamp acquiring
module 42, and a determining module 44.
The identifying module 40 is configured to identify a service flow
according to service flow characteristic information, and determine
whether the service flow is a target service flow.
Specifically, how to identify a service flow according to service
flow characteristic information has been described in detail in
Embodiment 6 of the method for measuring a network delay, and is
not described herein again.
The timestamp acquiring module 42 is configured to: if the service
flow is the target service flow, add a delay measurement flag to a
data packet of the service flow, and acquire data packet delay
measurement information corresponding to the delay measurement
flag.
Specifically, the timestamp acquiring module 42 adds a delay
measurement flag to a data packet of the target service flow, and
generates delay measurement information, where the delay
measurement information includes: timestamp information, a service
flow identifier, and a TLP identifier. The timestamp information is
a time point when the delay measurement flag is added by the TLP.
The service flow identifier and the TLP identifier have been
described in detail in Embodiment 1 of the method for measuring a
network delay, and are not described herein again.
The determining module 44 is configured to determine delay
measurement information, where the delay measurement information
includes: timestamp information, a service flow identifier, a TLP
identifier, so that after acquiring the delay measurement
information, the DCP transmits the delay measurement information to
an MCP.
The TLP according to this embodiment may be used to perform the
technical solution in Embodiment 6 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In the TLP according to this embodiment, optionally, the adding a
delay measurement flag to a data packet of the service flow by the
timestamp acquiring module 42, and acquiring data packet delay
measurement information corresponding to the delay measurement flag
includes that:
the timestamp acquiring module 42 of an upstream TLP is
specifically configured to add a delay measurement flag to the data
packet of the target service flow, and the timestamp acquiring
module acquires transmit-end delay measurement information of the
data packet corresponding to the delay measurement flag, where the
transmit-end delay measurement information includes: transmit-end
timestamp information, a service flow identifier, and a TLP
identifier, so that after acquiring the transmit-end delay
measurement information, a DCP managing the upstream TLP transmits
the transmit-end delay measurement information to the MCP.
The timestamp acquiring module 42 of a downstream TLP is
specifically configured to: when the identifying module identifies
the data packet to which the delay measurement flag is added, the
timestamp acquiring module acquires transmit-end delay measurement
information of the data packet corresponding to the delay
measurement flag, where the receive-end delay measurement
information includes: receive-end timestamp information, a service
flow identifier, and a TLP identifier, so that after acquiring the
receive-end delay measurement information, a DCP managing the
downstream TLP transmits the receive-end delay measurement
information to the MCP.
In one aspect, based on FIG. 11, FIG. 12 is a schematic structural
diagram of Embodiment 2 of a TLP according to the present
application. As illustrated in FIG. 12, the TLP further includes: a
time synchronization module 41 and a measurement period identifier
acquiring module 43.
When the TLP is an upstream TLP, the time synchronization module 41
is specifically configured to: before a timestamp acquiring module
42 of the upstream TLP adds the delay measurement flag to the data
packet of the target service flow, perform time synchronization
with the DCP managing the upstream TLP by using the NTP or an IEEE
1588v2 clock. When the TLP is a downstream TLP, the time
synchronization module 41 is specifically configured to: before an
identifying module 40 of the downstream TLP identifies the data
packet to which the delay measurement flag is added, perform time
synchronization with the DCP managing the downstream TLP by using
the NTP or an IEEE 1588v2 clock. The time synchronization methods
and principles have been described in detail in Embodiment 3 of the
method for measuring a network delay according to the present
application, and are not described herein again.
When the TLP is an upstream TLP, the measurement period identifier
acquiring module 43 is specifically configured to acquire a
measurement period identifier corresponding to the delay
measurement flag, so that after acquiring the measurement period
identifier, the DCP managing the upstream TLP transmits information
about the measurement period identifier to the MCP. When the TLP is
a downstream TLP, the measurement period identifier acquiring
module 43 is specifically configured to acquire the measurement
period identifier corresponding to the delay measurement flag, and
start time of each measurement period, so that after acquiring the
start time and the measurement period identifier, the DCP managing
the downstream TLP performs matching between the start time and the
measurement period identifier, and then transmits the receive-end
delay measurement information to the MCP.
It should be noted that, the DCP may directly read the delay
measurement information generated by the TLP, and the DCP may
acquire the corresponding measurement period identifier by using
the delay measurement information. In this solution, the upstream
TLP or the downstream TLP may not employ the measurement period
identifier acquiring module 43. In addition, with respect to the
TLP according to this embodiment, the TLP identifies the data
packet of the service flow based on each period, and adds the delay
measurement flag. Optionally, within each measurement period,
corresponding operations are performed on only one data packet.
The TLP according to this embodiment may be used to perform the
technical solution in Embodiment 8 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In another aspect, based on FIG. 11, FIG. 13 is a schematic
structural diagram of a TLP according to Embodiment 3 of the
present application. As illustrated in FIG. 13, the TLP further
includes: a transmitting module 46 and a receiving module 48.
The transmitting module 46 is specifically configured to transmit a
measurement packet to the downstream TLP by using a transmitting
module of the upstream TLP, where the measurement packet includes:
transmit-end timestamp information.
Specifically, after an identifying module 40 of the upstream TLP
adds the delay measurement flag to the data packet of the target
service flow, the timestamp acquiring module 42 adds the delay
measurement flag to the data packet, and acquires data packet delay
measurement information corresponding to the delay measurement
flag. In this case, the upstream TLP starts the transmitting module
46, and the transmitting module 46 transmits the measurement packet
to the downstream TLP.
The receiving module 48 is specifically configured to receive the
measurement packet by using a receiving module of the downstream
TLP, generate arrival timestamp information of the measurement
packet, and transmit the measurement packet and the arrival
timestamp information to the DCP managing the downstream TLP, so
that the DCP determines whether the arrival timestamp information
and the receive-end timestamp information pertain to a preset
duration range, and if the arrival timestamp information and the
receive-end timestamp information pertain to the preset duration
range, determines that the transmit-end timestamp information and
the receive-end timestamp information pertain to the same
measurement period, and transmits a result of the determining to
the MCP.
Specifically, the identifying module 40 of the downstream TLP
identifies the data packet with the delay measurement flag, and
generates corresponding receive-end timestamp information; the
receiving module 48 receives the measurement packet, records a time
point when the measurement packet is received, generates arrival
timestamp information, and transmits the measurement packet and the
arrival timestamp information to the determining module 44, so that
the determining module 44 transmits the measurement packet, the
receive-end delay measurement information, and the arrival
timestamp information to the DCP managing the downstream TLP;
therefore, the DCP managing the downstream TLP performs
corresponding operations.
In addition, in the method for measuring a network delay according
to this embodiment, the TLP identifies the data packet of the
service flow, with respect to each measurement period, the TLP adds
a delay measurement flag to the data packet within an interval of
the measurement period. Optionally, within each measurement period,
the TLP adds a delay measurement flag to only one data packet.
The TLP according to this embodiment may be used to perform the
technical solution in Embodiment 9 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In still another aspect, referring to FIG. 11, in a TLP according
to Embodiment 4 of the present application,
the transmit-end delay measurement information acquired by a
timestamp acquiring module 42 of the upstream TLP further includes:
transmit-end service flow characteristic information and a
transmit-end fragment reassembly identifier; and the receive-end
delay measurement information acquired by a timestamp acquiring
module 42 of the downstream TLP further includes: receive-end
service flow characteristic information and a receive-end fragment
reassembly identifier;
so that the DCP managing the upstream TLP acquires the transmit-end
delay measurement information and transmits the transmit-end delay
measurement information to the MCP, and the DCP managing the
downstream TLP acquires the receive-end delay measurement
information and transmits the receive-end delay measurement
information to the MCP; therefore, the MCP determines, according to
the transmit-end service flow characteristic information, the
transmit-end fragment reassembly identifier, the receive-end
service flow characteristic information, and the receive-end
fragment reassembly identifier, whether the transmit-end timestamp
information and the receive-end timestamp information are timestamp
information corresponding to a same service flow.
The TLP according to this embodiment may be used to perform the
technical solution in Embodiment 10 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
Optionally, in Embodiment 1 to Embodiment 4 of the TLP according to
the present application, the adding, by the timestamp acquiring
module of the upstream TLP, a delay measurement flag to the data
packet of the target service flow includes: adding, by the
timestamp acquiring module, a delay measurement flag in a reserved
bit of TOS or a reserved bit of Flags in an IP header of the data
packet. In this way, the delay measurement flag may be added to the
data packet by using the reserved bit of TOS or the reserved bit of
Flags, and normal transmission of the data packet is ensured.
In addition, the identifying module 40 is specifically configured
to identify the service flow according to information about at
least two tuples in a quintuple, to ensure effective identification
of the service flow.
Specifically, the reserved bit of TOS or the reserved bit of Flags,
and the quintuple have been described in detail in Embodiment 7 of
the method for measuring a network delay according to the present
application, and are not described herein again.
FIG. 14 is a schematic structural diagram of Embodiment 1 of an MCP
according to the present application. As illustrated in FIG. 14,
the MCP includes: a receiving module 70 and a determining module
72.
The receiving module 70 is configured to receive transmit-end delay
measurement information transmitted by a DCP corresponding to an
upstream TLP and receive-end delay measurement information
transmitted by a DCP corresponding to a downstream TLP, where the
transmit-end delay measurement information includes: transmit-end
timestamp information, a service flow identifier, and a TLP
identifier; and the receive-end delay measurement information
includes: receive-end timestamp information, a service flow
identifier, and a TLP identifier;
The determining module 72 is configured to determine details about
a single network delay according to the transmit-end delay
measurement information and the receive-end delay measurement
information.
Specifically, the MCP is deployed on any network element node
device on the network, and operationally deployed on a network
element node device with powerful functions. The determining module
72 maintains a measurement data summary table for a target service
flow. For details, refer to Table 1. The specific calculation
principles and formulas employed by the determining module 72 have
been described in detail in Embodiment 12 of the method for
measuring a network delay according to the present application, and
are not described herein again.
The MCP according to this embodiment may be used to perform the
technical solution in Embodiment 11 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In one aspect, based on FIG. 14, FIG. 15 is a schematic structural
diagram of Embodiment 2 of an MCP according to the present
application. The MCP includes: a receiving module 70 and a
determining module 72, where the receiving module 70 includes a
first receiving unit 700 and a second receiving unit 702. The
determining module 72 includes: a first matching unit 720 and a
first determining unit 722.
The first receiving unit 700 is specifically configured to receive
the transmit-end delay measurement information transmitted by the
DCP corresponding to the upstream TLP and the receive-end delay
measurement information transmitted by the DCP corresponding to the
downstream TLP, where the transmit-end delay measurement
information includes: transmit-end timestamp information, a service
flow identifier, and a TLP identifier; and the receive-end delay
measurement information includes: receive-end timestamp
information, a service flow identifier, and a TLP identifier.
The second receiving unit 702 is specifically configured to receive
a measurement period identifier transmitted by the DCP managing the
upstream TLP, and receive a measurement period identifier
transmitted by the DCP managing the downstream TLP.
The first matching unit 720 is specifically configured to
determine, according to the measurement period identifier
transmitted by the DCP managing the upstream TLP and the
measurement period identifier transmitted by the DCP managing the
downstream TLP, whether the transmit-end delay measurement
information and the receive-end delay measurement information
pertain to a same measurement period.
Specifically, after the second receiving unit 702 receives the
measurement period identifier, the first matching unit 720 updates,
according to the measurement period identifier transmitted by the
DCP managing the upstream TLP and the measurement period identifier
transmitted by the DCP managing the downstream TLP, the
transmit-end delay measurement information and the receive-end
delay measurement information that pertain to a same measurement
period to corresponding entries in the measurement data summary
table for the target service flow that is maintained by the
MCP.
The first determining module 722 is specifically configured to: if
the transmit-end delay measurement information and the receive-end
delay measurement information pertain to a same measurement period,
determine details about a single network delay according to the
transmit-end delay measurement information and the receive-end
delay measurement information.
Specifically, after the first determining unit 722 detects that a
data arrival flag of a data entry corresponding to a forward
service flow identifier or a backward service flow in a measurement
period identifier in Table 1 is set to "All arrive", the first
determining unit 722 performs delay calculation according to the
corresponding transmit-end timestamp information and the
corresponding receive-end timestamp information. The specific
calculation principles and formulas have been described in detail
in Embodiment 12 of the method for measuring a network delay
according to the present application, and are not described herein
again.
The MCP according to this embodiment may be used to perform the
technical solution in Embodiment 12 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In another aspect, referring to FIG. 12, an MCP according to
Embodiment 3 of the present application includes: a receiving
module 70 and a determining module 72.
The receiving module 70 is specifically configured to receive the
transmit-end delay measurement information transmitted by the DCP
corresponding to the upstream TLP, and the receive-end delay
measurement information that is determined as pertaining to a same
data packet as the transmit-end delay measurement information and
is transmitted by the DCP corresponding to the downstream TLP.
The determining module 72 is specifically configured to determine
details about a single network delay according to the transmit-end
delay measurement information and the receive-end delay measurement
information.
Specifically, the DCP may transmit the matched transmit-end delay
measurement information and receive-end delay measurement
information to the MCP, the receiving module 70 of the MCP receives
and updates the transmit-end delay measurement information and the
receive-end delay measurement information to data entries of the
corresponding data packet, and the determining module 72 determines
details about a delay. The DCP may also determine details about a
delay according to the matched transmit-end delay measurement
information and receive-end delay measurement information, and then
transmits the determined details about a delay to the MCP. In this
case, the receiving module 70 of the MCP directly receives the
details about a delay, and the determining module 72 does not need
to be started.
The MCP according to this embodiment may be used to perform the
technical solution in Embodiment 13 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
In still another aspect, based on FIG. 14, FIG. 16 is a schematic
structural diagram of Embodiment 4 of an MCP according to the
present application. As illustrated in FIG. 16, the MCP includes: a
receiving module 70 and a determining module 72.
The receiving module 70 is specifically configured to: receive the
transmit-end delay measurement information transmitted by the DCP
corresponding to the upstream TLP, where the transmit-end delay
measurement information includes: the timestamp information, the
service flow identifier, the TLP identifier, transmit-end service
flow characteristic information, and a transmit-end fragment
reassembly identifier; and receive the receive-end delay
measurement information transmitted by the DCP corresponding to the
downstream TLP, where the receive-end delay measurement information
includes: the timestamp information, the service flow identifier,
the TLP identifier, receive-end service flow characteristic
information, and a receive-end fragment reassembly identifier.
The determining module 72 includes: a second matching unit 721 and
a second determining unit 723.
The second matching unit 721 is specifically configured to
determine, according to the transmit-end service flow
characteristic information, the transmit-end fragment reassembly
identifier, the receive-end service flow characteristic
information, and the receive-end fragment reassembly identifier,
whether the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same data packet. The specific working principles and methods have
been described in detail in Embodiments 5, 10, and 14 of the method
for measuring a network delay according to the present application,
and are not described herein again.
The second determining module 723 is specifically configured to: if
the transmit-end timestamp information and the receive-end
timestamp information are timestamp information corresponding to a
same data packet, determine details about a single network delay
according to the transmit-end delay measurement information and the
receive-end delay measurement information. The specific working
principles and methods have been described in detail in Embodiments
5, 10, and 14 of the method for measuring a network delay according
to the present application, and are not described herein again.
The MCP according to this embodiment may be used to perform the
technical solution in Embodiment 14 of the method for measuring a
network delay according to the present application. The
implementation principles and technical effects are similar, and
are not described herein again.
FIG. 17 is a schematic structural diagram of Embodiment 1 of a
system for measuring a network delay according to the present
application. As illustrated in FIG. 17, the system according to
this embodiment includes: DCPs, TLPs, and an MCP. Optionally, a
random quantity of TLPs are deployed on both sides of a network,
and DCPs are deployed correspondingly. This embodiment sets no
limitation to the quantity of TLPs and that of the corresponding
DCPs. The DCPs may employ the structures illustrated in FIG. 8 to
FIG. 10, and may correspondingly perform the technical solutions in
Embodiment 1 to Embodiment 5; the TLPs may employ the structures
illustrated in FIG. 11 to FIG. 13, and may correspondingly perform
the technical solutions in Embodiment 6 to Embodiment 10; the MCP
may employ the structures illustrated in FIG. 14 to FIG. 16, and
may correspondingly perform the technical solutions in Embodiment
11 to Embodiment 14. The implementation principles and technical
effects of the DCPs, the TLPs, and the MCP are similar, and are not
described herein again.
FIG. 18 is a schematic diagram of Embodiment 2 of a system for
measuring a network delay according to the present application.
Referring to FIG. 17 and FIG. 18, the following comprehensively
describes the method, apparatus, and system for measuring a network
delay according to the present application.
Referring to FIG. 18, TLPs are deployed a network side of an
upstream transmit end and a downstream receive end. Optionally, the
TLPs may also be deployed on a user side, and DCPs are deployed on
devices at the upstream transmit end and those at the downstream
receive end. Referring to FIG. 18, when a target service flow is in
a direction from left to right, a cell site gateway CSG (Cell Site
Gateway, hereinafter referred to as CSG) is the upstream
transmit-end device, radio network controller site gateway RSG
(Radio Network Controller Site Gateway, hereinafter referred to as
RSG) 1 and RSG 2 are the devices at the downstream receive end; and
when the target service flow is in a direction from right to left,
reverse setting is performed for the upstream and the downstream.
The specific technical solution has been described in detail in
Embodiment 12 of the method for measuring a network delay according
to the present application, and is not described herein again. In
addition, an MCP is deployed on any network element node on the
entire network. For example, as illustrated in FIG. 18, an MCP is
deployed on RSG 1. Optionally, the MCP may be deployed on a network
element node with powerful functions, and a transmission path of
delay measurement information is differentiated from a transmission
path of the target service flow for out-band transmission, thereby
ensuring independence in optionally reading and transmitting the
delay measurement information. A management network (as illustrated
in FIG. 18, a path of a management network layer is represented by
dotted lines) may employ a Layer 3 measurement VPN, a DCN, or a
public network with reachable IP addresses.
When a network delay is enabled, the TLPs, the DCPs, and the MCP
cooperate to directly measure the delay of the service flow. The
specific methods and technical solutions have been described in
Embodiments 1 to 14 of the method for measuring a network delay
according to the present application, Embodiments 1 to 4 of the DCP
according to the present application, Embodiments 1 to 4 of the TLP
according to the present application, and Embodiments 1 to 4 of the
MCP according to the present application, and are not described
herein again.
Some networks are hybrid networks including a Layer 2 VPN network
and a Layer-3 VPN network. Because the Layer 2 VPN network and the
Layer 3 VPN network have different measurement criteria, with
respect to this network scenario, there is no feasible and
effective delay measuring method in the prior art. As can be
learned from Embodiment 1, with respect to acquisition and
transmission of the delay measurement information between the TLPs,
the DCPs, and the MCP according to the embodiments of the present
application, out-band transmission is implemented by means of
transmission on the management network, thereby effectively
preventing the problem of delay measurement information due to
different measurement criteria of the Layer 2 VPN network and the
Layer 3 VPN network.
Referring to FIG. 18, with respect to a dual-homing access scenario
of devices RSG 1 and RSG 2 on the right side of the network, when
path switching occurs on RSG 1 and RSG 2, because delay measurement
information according to the embodiments of the present application
includes: timestamp information, a service flow identifier, and a
TLP identifier, in cases of switchover between RSG 1 and RSG 2, a
TLP on a new receive device performs delay measurement on a data
packet of a target service flow. For example, when the target
service flow is originated from a left-side user, the TLP on the
CSG identifies the target service flow, enables network delay
measurement, and subsequently the target service flow passes
through the network to arrive at the TLP on RSG 1. The TLP on RSG 1
performs corresponding receive-end delay measurement. When the RSG
1 encounters a fault, the target service flow is switched to RSG 2.
In this case, the TLP on RSG 2 may identify the target service flow
and continuously perform the corresponding delay measurement.
Persons of ordinary skill in the art may understand that all or a
part of the steps of the method embodiments may be implemented by a
program instructing related hardware. The program may be stored in
a computer readable storage medium. When the program runs, the
methods of the method embodiments are performed. The foregoing
storage medium includes: any medium that can store program code,
such as a ROM, a RAM, a magnetic disk, or an optical disc.
Finally, it should be noted that the foregoing embodiments are
merely intended for describing the technical solutions of the
present application, but not for limiting the present application.
Although the present application is described in detail with
reference to the foregoing embodiments, persons of ordinary skill
in the art should understand that they may still make modifications
to the technical solutions described in the foregoing embodiments
or make equivalent replacements to some or all technical features
thereof, without departing from the scope of the technical
solutions of the embodiments of the present application.
* * * * *